


So Much More

by Mercy_Run



Category: Undertale (Video Game)
Genre: Angst, Angst with a Happy Ending, Child Abuse, Depression, Dubious Soul Fondling, F/F, Fontcest, M/M, Masturbation, Origin Story, Papyrus is naive not stupid, Papyrus may have an oral fixation, Resets, Revised Plot, Self-Hatred, Skeleton Brother Backstory, Smut, Violence, evil gaster, self-neglect
Language: English
Status: Completed
Published: 2016-11-07
Updated: 2017-01-27
Packaged: 2018-08-29 17:17:36
Rating: Explicit
Warnings: Underage
Chapters: 16
Words: 27,261
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8498500
Author URL: https://archiveofourown.org/users/Mercy_Run/pseuds/Mercy_Run
Summary: A story of two brothers, from youth through adulthood.  Sans was so glad that he had heard that he had a brother, flinching as he fed magic directly into the tiny, barely glowing orange soul.  The baby skeleton was staring up at his young face, emitting distressed whimpers at the pained expression that he couldn't help.  Sans had almost been too late, ignoring his health gauge; which was dropping from 20 very quickly.  Finally, when his vision was beginning to blur out, Papyrus let out a muffled wail into his shoulder as his soul stabilized."don't worry, papyrus.  big brother has you."  Sans whispered, his maximum health settling at one forever for his reckless move, "you won't be alone anymore, i will take care of you."





	1. Chapter 1

\---------------  
Current Ages:  
Sans-5  
Papyrus-1  
\----------------

Sans had accepted early on that pain was a huge part of his life. The first few years of his young life was spent wondering why the only parent he knew never smiled at him, never hugged him or told him that he was loved. The first memories Sans had taught him it was best not to ask for these things. Asking only made things worse. Crying had made his father strike and yell at him.

So at the tender age of five, Sans had made his peace with the hand he had been dealt. Dr. Gaster, because he couldn't call him 'Dad', was just a cold monster. Work meant everything to the scientist, so in an attempt to connect; Sans had turned his questions of 'where is my mom' and 'why don't you love me' to 'what is a molecule' and 'how is your project going'?

Gaster's response was initially disdain but after the young skeleton buried himself in books, his father begrudgingly began to teach him. They moved completely into the lab from the house Sans had lived in alone and proved himself to be a quick learner. He must have proven himself so much that Gaster expected him to work beside him. Sans had even grabbed a side job from a monster that had noticed the skeleton often wasn't fed because Dr. Gaster would forget.

The monster in human resources never mentioned Sans getting paid for cleaning the lab at night. They never mentioned the neglect to anyone as even the small skeleton looked panicked when they had brought it up once. It was something strictly under the table. Anyone who worked in the labs had Gaster as a boss, so all of the employees guiltily ignored any abuse in fear of their jobs.

Sans worked diligently beside Dr. Gaster during the day and cleaned during the night. Sometimes he worked the entire night and had to skip out on sleep.

It was only by this fact that he overheard some monsters talking, pausing on his way around the corner; lab coat dragging the floor behind him.

"That woman that came in here... do you think she really meant to go through with her threat?" It was the voice of the winged professor that dealt with new biology students.

"What? You mean the monster from a few days ago?" It was the human resources monster that got Sans his job, her huge eye blinking, "probably. You haven't worked here as long as I have, so you wouldn't have recognized her."

"That...shouldn't we warn someone then? Who is she?" The professor questioned.

"That was-" Sans had to lean slightly closer as her voice dropped, "that was Gaster's lover. Must be an off and on again type of thing; she is little Sans' mom."

The skeleton felt his soul drop. His mother? She had been here and hadn't even cared to seek him out? Sans' expression dropped. Then...his... Dr. Gaster must have been telling the truth when he had said she didn't care about him.

"S-Sans...? Then, the baby she threatened to leave is probably..." The professor trailed off and the other monster finished for him.

"Yeah, most likely his younger brother." She murmured quietly and Sans' eye sockets widened. He had a brother? The rest of the statement sunk in then and he bit his index finger uncertainly. Leave his younger brother? He didn't understand, leave him here? Abandon him like she had with Sans? He listened to the conversation intently, anxious white pupils darting down the hallway he had come from to check if anyone noticed he was eavesdropping.

"Should we alert the guard? Or maybe check out the house? Snowdin isn't very far from here, just a boat-ride away..." The professor trailed off when the other monster hushed him.

"Gaster would fire us for just talking about this. What do you think he would do if we interfered in his personal life?"

The silence that stretched out from there was all of the answer Sans needed. They wouldn't intervene. They were too afraid. Sans gasped in air as he made his way back the hallway he had come. His mother had left his baby brother alone. Gaster didn't care about the child. Without hesitation, the skeleton took the elevator up to the lobby above and left the lab proper. Sans hurried across the hot ground and took the stairs down to the boat he had spotted before.

Sans knew that he was defying what Dr. Gaster wanted, but he didn't care. He boarded the boat, soul pounding with anxiety as he had never been out of the Hotlands before.

"i-i need to get to snowdin..." Sans told the Riverperson, who was cheerful and thankfully didn't ask questions. He gripped the seat he was on tightly as the cloaked figure sang; the boat made swift with magic.

"Tra la la, the water is rather dry today." They said blissfully and the small skeleton blinked in confusion before gasping at the temperature change. Sans looked upwards, marveling at his first encounter with snow before the boat slid to a halt.

"We are here," Riverperson declared and Sans stood.

"how much do i owe you?" He asked quietly and the cloaked figure tilted their head at the child.

"The boat rides are free, la la la," they insisted and Sans thanked them before jumping out into the snow. It soaked the part of his lab coat that touched the ground and Sans shivered, making his way into the town. It was dark here, no lava to light his way; but a sign caught his attention and the skeleton trudged through the snow towards it.

The neon sign read 'Grillby's' and Sans could tell that this was a business. White pupils widened when the door opened to let some dogs dressed in armor out, a flame elemental guiding them. Sans cringed back when the tall, well dressed monster noticed him; adverting his gaze to the ground in a hurry.

A beat of silence passed before the taller monster spoke.

"You look like you could use someone to talk to." The voice was deep, gentle; crackling with each word and the skeleton raised his eyes to the other's face.

"i-i'm looking for someone...actually..." Sans managed, trembling. The monster paused and then straightened, changing his sign from 'open' to 'closed'.

"Come in. It's much warmer in here, son." It might have been the stress of everything, or just being referred to as 'son' for the first time in his life, but Sans took the stranger's gloved hand when he offered without hesitation.

"I am Grillby, what is your name?" The elemental questioned as the small skeleton soaked up the warmth offered by being inside and so close to the elemental.

"sans." He answered simply.

"It's nice to meet you, Sans. Who are you looking for?" Grillby questioned gently as he examined the young monster. There was something in the shadows under the child's eye-sockets and demeanor that screamed abuse. It was hard for him to tell the small skeleton's age. His manner of speech was so mature in contrast to his body.

"some of the people i work with said my...my mom abandoned my younger brother somewhere in town." Grillby's flame sparked in surprise. This child worked?! He did another quick once over of the skeleton. He was certain this was a child monster, even with lack of a striped shirt.

"do you know where she lived?" Sans continued, the silence that stretched between them making him uncomfortable. Grillby straightened, embarrassed that he had let his polite demeanor slide.

"Apologies, Sans. There was a skeleton monster that had a child here, but I think they moved. Still, the log cabin down the main road belonged to them... The two story one, with Christmas decorations still up," he turned towards the bar to check his calendar and jumped in surprise when his front door slammed shut.

The bartender considered following the child but refrained. Surely if he needed something, Sans would be back?

The cold stung his sensitive bones as the skeleton raced down the main road until he discovered the house that matched Grillby's description. Puffing out frosty breaths, Sans noted that all of the windows were dark and the lights outside weren't even lit up. Frowning, he pressed up against the front door but couldn't hear anything.

He made a small motion, finger lighting up a soft blue hue and the lock on the inside 'snicked' open. Sans tensed before opening the front door and entering the house; cringing at the messy state that greeted him. It looked like everything of worth had been taken away in a hurry, bags of diapers soiled with magical discharge partially open and littering the floor.

Sans closed his eye sockets and strained his hearing. It was quiet, much too quiet. Had his mother changed her mind and took his brother with her?

A tiny whimper from the second level had him running up the stairs, tripping on his long lab coat before he forced the first door open. Breath hitching, Sans took in the tiny infant skeleton; who was laying on a magic soiled crib without a scrap of clothing to protect him from the cold. The baby weakly peered in his direction, the small soul in his rib cage dimming.

"brother..." Sans' eye sockets widened and he crossed the room; scooping up the baby without care of the mess. The baby was so tiny and he wasn't moving very much, merely emitting soft distressed noises. The dim soul was shuddering and the infant's eyes closed, barely there gasps fighting for air.

No...No...He wouldn't let his brother die! Sans held the baby close and focused on his own soul. He had only studied this but the skeleton focused on his Intent, building it up until his soul glowed like a beacon and then gently, oh-so-carefully began to feed his magic into the flickering soul.

19/20...18/20...17/20

The infant shuddered and opened it's eye sockets to stare up at his face; his raw magic surrounding the inverted heart. Sans couldn't find the energy to reassure the baby when his expression twisted into pain, the blue magic surrounding and filtering slowly into his baby brother.

16/19... Oh no...! He was doing it wrong, but Sans wasn't going to stop now. The other's soul was growing a little brighter, revealing itself to be a vivid orange hue. He closed his eye sockets and held the baby close trying to focus on life and health instead of the pain spiking up his spine.

He opened them when his brother wiggled in his hold, his vision swimming; ignoring the health gauge altogether in favor of taking in the other's features. The pain was so bad that he bared his small fangs in agony, searching the room a moment later instead because the baby seemed distressed by his facial expressions.

Small word blocks were on a table, spelling out 'Papyrus'.

He forced his fangs together and looked down at his brother, the soul finally stabilizing and glowing a strong orange. Sans panted as he stopped the flow of magic.

1/1

Deep breaths, he thought desperately, rocking his tiny brother. It didn't matter, Gaster never checked his stats. He wouldn't know Sans had done anything.

A tiny hand fisting his shirt brought the skeleton's attention back down to the baby. His brother, Papyrus; was watching his expression intently and Sans schooled his pained expression into a genuine tender smile.

"h-hey there, papyrus..." He whispered and the infant blinked before smiling up at him, as if he wasn't covered in filth and had been so close to death a moment before. Sans chuckled and brought the baby up, leaning their skulls together.

"i'm your big brother. i'm sans." He greeted and Papyrus cooed in response. He stood and cradled his brother carefully; walking through the house and testing the water. It was still working and Sans tested the temperature until the sink was full of lukewarm water. Papyrus watched his face with an attentive smile as he carefully began to wash magic discharge from the tiny bones. There had to be at least a few clean diapers here. If not, Sans had brought his spare money along...

"i don't know much about babies," he told the skeleton as he wiggled in his hold, making a face at the water that made Sans laugh in response, "but i will take care of you. i promise."

Papyrus lifted his face from the cloudy water and smiled brightly; as if he understood. Hopefully it was just a social instinct, Sans really didn't want his brother to remember being abandoned. He didn't want his brother to remember any of this. In fact...

"i will protect you, lil' bro. no one will hurt you from now on. i swear." He toweled Papyrus off and sure enough, after searching around; he found some clean diapers. After trial and error, Sans managed to get one on. There were no clean blankets or clothes, but he found the power source for the house and flipped the switch.

Sans carried his suddenly sleepy brother around the house, checking the refrigerator and finding some empty baby bottles inside along with spoiled milk. Papyrus was sleeping now, but the older brother figured he would be hungry very soon.

A knock made him freeze, his soul pounding as the front door opened slowly. Sans' left socket flared with blue flames as he held out his free hand protectively.

He froze as Grillby entered slowly, stopping once he noticed Sans prepared to attack him. The elemental took in the state of the house and the child's protective expression, as well as the freshly diapered baby.

"Sans..."

The skeleton child bared his fangs, outstretched hand pulsing blue.

"if you think you are going to separate us, think again." Sans snarled quietly so he wouldn't alert Papyrus, sockets narrowing. Grillby held out both hands in a pacifying gesture.

"I only want to help you, son." He whispered, "I can help you go back to your family..." His crackling voice trailed off as Sans' magic glowed brighter in warning.

"my...my father knew papyrus had been abandoned and did nothing. i won't let him anywhere near my brother."

Grillby hesitated, "Sans...does your father hit you?"

The silent tears welling up in the child's eyes was answer enough.

"...How old are you, son?" The elemental questioned gently. Sans glared, left eye pulsing.

"Five."

Younger than he had thought...

"You are twelve now, Sans." The puzzled expression had him continuing, "the minimum age requirement to work is twelve. I don't start serving alcohol until four. Young workers can work the morning and lunch shift."

"...why are you telling me this?" The skeleton questioned.

"You need a stable job if you plan on taking care of your sibling." Grillby murmured quietly. Slowly, the magic licking the other's hand faded and Sans lowered his arm, eye-lights returning to normal.

"i still need to return to the lab at least an hour a day," Sans returned quietly. Grillby looked at the other's attire and frowned. There was only one adult skeleton monster other than the woman who left that he knew of in the Underground. The elemental didn't want Sans returning to that man but merely nodded.

"Here, let me help you clean this mess up. There is a shop still open at the very beginning of town that will have things you need." Grillby helped the child skeleton clear out the mess, subtly cleaning up more because Sans refused to let go of Papyrus. Once the spoiled food, broken furniture and fair amount of bags filled with dirty diapers were cleared out; the house was barren save for Papyrus few toys and crib.

Sans was stroking his brother's spine slowly and raised a guilty gaze to the adult monster.

"grillby...thank you. for letting me take care of my brother on my own." The way Sans was clinging to the infant spoke volumes. This child wasn't used to kindness and he was terrified his only family that cared about him was going to be taken away.

"It's no problem, Sans. This is going to be hard for you, offering you work is the least I can do. Now, let me go pick up some things from the shop," Grillby told the skeleton child who forced him to take his savings along. The elemental counted the money and sighed inwardly. It was obvious from the gold pieces that they had been in the bag for a good time, their surfaces nicked. It was a fair amount of money. Plenty enough for warm blankets, milk, diapers and food. Sans must rarely spend anything on himself...

Idly, Grillby decided that Sans should have a tab at his bar so he could watch the child eat at least once a day to look after his health. Not that he would keep count or even let Sans pay it.


	2. Chapter 2

\---------------

Current Ages:  
Sans-6-7  
Papyrus-2-3

\----------------

Raising his young brother was equal parts hard, terrifying and rewarding. When he had initially returned to the labs during one of Papyrus' naps; Gaster hadn't even noticed Sans had been missing. So, his days were filled of working with Grillby in the morning, dropping by the lab whenever the baby skeleton would fall asleep and then work at a hot dog stand in the Hotlands.

At first, it had been rather easy; even though Sans was always exhausted. Papyrus was a good baby, who slept more often than not. The only things he required was diaper changing, playing, plenty of cuddles and feeding. Sans loved Papyrus, the infant was his world. He had no one else but his baby brother. No friends to hang out with, no other family that cared. All he needed was Papyrus. Grillby was a good employer and friend, but Sans longed for his downtime, when he would scribble on blueprints in the workshop around the back of the house, Papyrus' tiny body huddled against his shoulder.

But when Papyrus began to crawl and then walk around was when things started to become more difficult. The older brother ran himself ragged with work and worrying over his young bro, who had suddenly gotten so much energy that it was nearly frightening.

Papyrus would often get into things that might hurt him, falling from places higher than Sans was comfortable with, giggling as the other skeleton cried 'pap, no!' as he used gentle gravity magic to right the situation. Sans wasn't sure what drove his tiny brother to get into so much mischief, but his happy and carefree smile would wash away his anxiety instantly.

Papyrus was a happy baby. A difficult baby, but happy. And that was what mattered most to Sans. He never got angry or raised his voice at the child; he was too precious for that. Too good for that.

Even when, to Sans' mortification, Papyrus' first word had been 'no'!

Maybe, in hindsight, crying the other's name along with 'no' every time he got himself into trouble had been a mistake. The women who had children of their own would give the small skeleton pitying looks as Papyrus happily repeated 'no, no, no'!

Sans didn't mind. Papyrus was happy. That was all that mattered.

He returned to their house, which now had toys all over the living room, the crib moved down here where it was warmer. Sans sat his brother down in the crib.

"Nooooo..!" Papyrus drew out mournfully and Sans chuckled.

"no? but i am getting you some baby food, bro. don't you want some?" The skeleton child teased, warming up the goop.

"NO!" Papyrus insisted more zealously.

"you aren't hungry? but i just fixed this for you." Sans chuckled, showing the other the bowl, picking out a spoon.

"NOOOOO!" The infant wailed.

"guess i will just have to eat it then..."

"Sa-ans!!!" 

Eye sockets widening, the spoon clattered to the floor as the skeleton stared at the pouting baby in shock.

"w...what did you just say?" He questioned, voice strangled. Papyrus pouted and reached out both arms.

"Sans!" The word wasn't broken this time and startled, joyful laughter burst past Sans' fangs. He carefully selected another clean spoon and sat in front of Papyrus, who was beaming in reaction to his older brother's laughter.

"y-you said my name," he ran a gentle hand over the other's skull, "i am so proud of you, papyrus."

The child beamed in response and Sans began to feed him; murmuring how happy he was whenever Papyrus would glance at him when he was too quiet.

\---------------

Current Ages:  
Sans-8-9  
Papyrus-4-5

\----------------

When Papyrus' vocabulary expanded, then came a new favorite. 'Why'? His little brother was full of questions and Sans was happy to answer them. The little one stayed awake more, so Sans had to cut back on how much sleep he got at night to fit his jobs and Papyrus neatly. Papyrus was his priority and his jobs were important to take care of the child.

Grillby noticed how Sans' eyes now had what seemed like permanent dark circles burned under his sockets. He suggested enrolling his baby brother into school and Sans had grinned at the suggestion. His soul had nearly broken when Papyrus refused to let go of him to leave for his first day, but Sans was happy when the other came back, cheerful and eager to tell what had happened.

The young skeleton dedicated all of the hours Papyrus was at school to his work. Gaster had proposed a new project that often had Sans in his workshop overnight. He did have a real love for science, regardless of how it had began.

Time travel was such an interesting concept.

One day, he entered the lab after he had dropped Papyrus off at school and froze. Dr. Gaster was waiting in the lobby for him.

"Sans, I need to speak with you."

The cold tone made Sans hesitate but he nodded all the same. The long and silent trek to Gaster's office made the child skeleton afraid. It wasn't often he was called from his work and never alone. The Royal Scientist locked the door of the office behind them and motioned sharply to the available chair.

"Sit."

Sans immediately sat down and tensed when he was circled instead of his father taking the seat behind his desk.

"I am very disappointed in you, Sans." The scientist hissed and the child skeleton panicked. Where had he messed up?! Had he messed up a project somehow?

"Wha..what?" Sans questioned quietly. Gaster loomed over his small body.

"Playing house in Snowdin renders you useless here!"

Sans' soul dropped. Oh stars...no...

"Your research is suffering because you are wasting time on that worthless bundle of bones."

Anger flared in the child and his sockets narrowed, "don't talk about my brother lik-UGH!" His face snapped to the side as the Royal Scientist back-handed him.

"And since your research is suffering, I will have to use you in more productive ways." Gaster continued like he hadn't even spoken. He strolled over to his desk and opened one of the drawers as Sans' watched with terrified eyes, one hand cradling his bruised bone. Slender fingers tapped at a syringe filled with vicious-looking green liquid.

"What...what is that...?" Sans whispered and the other merely advanced.

Sans had accepted early on that pain was a huge part of his life. He just hadn't realized how painful things could be before now. He thrashed, screaming and fighting as Gaster injected something that made every bone in his body ignite with an unquenchable fire. He trembled and was struck more times than he could count in kind for any violence he tried against the Doctor. How he didn't lose his single HP was a wonder. 

Trembling, he submitted finally; too battered and afraid to do anything more.

"If you don't want me to seek out your 'brother'," the word was drawn out mockingly, "you won't fight me when I want to use you for tests. That is all you are good for. You are useless otherwise. Understood?"

Sans whimpered, nodding behind the arms he had brought up to protect himself.

That night, Sans thanked all of the stars that Papyrus was already snoozing away in his new race-car bed when he arrived home. Thick, teal tears spilled down his face as he quietly shut his little brother's door. Once sealed into his room, he curled up in the blankets, crying silently as he focused his unstable magic on healing his visible bruises. His left eye flared and sputtered but Sans didn't make a noise.

Papyrus shouldn't know. He shouldn't ever know. Sans loved him too much to let even a hint of cruelty to reach his younger sibling.

So at nighttime, he allowed himself to hurt and then greeted Papyrus during the day as normal.

His brother was happy and nothing else but that mattered.

\---------------

Current Ages:  
Sans-10-11  
Papyrus-6-7

\----------------

"Sans! Brother! Measure me!" Papyrus insisted as his older brother walked into the door with a tired smile. Thankfully it was his job at the Hotlands that he was coming back from. The child, who now came up to his waist waved a measuring tape in the air.

"what's that, papyrus?" The older skeleton questioned, cocking his head and trying not to look tired at all. Sans didn't want Papyrus to worry. The other bounced excitedly, dressed in his favorite orange striped shirt and jeans, his sneakers thudding on the carpet.

"I learned this today at school! You lean against a doorway and mark your height! Please, brother!" Papyrus cried with a smile. Sans chuckled and took the measuring tape. He couldn't deny his younger bro anything, especially when he was wearing that expression.

"heh, okay, pap. come here." He motioned to the front door and Papyrus straightened his small spine, as if trying to be as tall as he could possibly be. Sans pulled the measuring tape up the door and marked when the crown of his sibling's skull ended. Checking the tape, he marked down 3'6 with a smile. Papyrus jerked back and beamed up at him.

"YOU NEXT!" He insisted and Sans gave in with a grin, helping Papyrus hold the tape as far as his reach would go. Sans felt the back of his head and drew a line and then pulled the tape up the rest of the distance.

"Wowie, Sans! Four feet, four inches. You have beaten me!" The energetic child declared. Sans laughed and shook his head, laying a gentle hand on top of Papyrus' skull.

"this isn't a competition, bro. we can do this every year, mark your growth. it will be a good memory." He smiled as Papyrus beamed up at him happily. 

Sans blinked in surprise when the other's strong smile eased into uncertainty.

"Sans...am I not normal?" The timid question had Sans kneeling down on Papyrus' level in the blink of an eye, his hands cupping the other's tiny shoulders.

"of course you are, papyrus! Who told you weren't normal?" He questioned anxiously. The orange clad skeleton hummed uncertainly.

"No one has really told me that...but I don't have a lot of friends. I thought maybe something was wrong with me..."

"papyrus..." Sans' tilted his younger brother's face up, "you are wonderful. great. the best. i am sure that friends will come to you naturally. there is absolutely nothing wrong with you."  
His solemn tone seemed to have caught Papyrus' full attention.

"Really?!" The skeleton child questioned and Sans smiled genuinely.

"really, really. i wouldn't lie to you, pap." He pulled the smaller body into an embrace, "i love you, bro."

"I love you too, Sans." His younger brother returned happily.

\-----

The world blurred in and out for Sans; the only thing he had to keep himself grounded was the level, droning tone of Dr. Gaster.

"Subject's HP remains at one, but appears to have the resilience to withstand more pain than the average monster without turning to dust. Serum 035 was injected directly into the soul instead via bones; effects intensified. Duration slightly longer but the experiment isn't yielding the proper results."

Sans blinked his eye sockets slowly, trying to ignore the intense pain wracking his body. He didn't fight anymore. His hazy mind brought his younger brother to mind. Papyrus ...Papyrus was everything to him.

The memory of his laughter, his smile and his zeal for life was enough for the child skeleton to hang in there.

"Now injecting Serum prototype 036..."

Sans closed his eyes in resignation and allowed the agony to pull him back under.

\---------------

Current Ages:  
Sans-12-13  
Papyrus-8-9

\----------------  
"SANS! SANS!" The skeleton stopped in his tracks, glancing behind him as he waited for Papyrus to appear. Surprisingly, his young brother was pulling another monster by the hand. She looked to be a bit older than Pap, one of her eyes covered by a patch and her features aquatic. Not surprising, since they were in Waterfall. 

"Look, brother! I made a friend!" Papyrus declared happily, motioning to the girl, "her name is Undyne and her magic is so cool! She can make spears!"

Sans looked at the girl, who was frowning softly with her eye flickering over to Papyrus. The older brother recognized the emotion there. The monster was lonely, something that he could fully understand. He returned his attention back to Papyrus and smiled, holding out his umbrella to protect the two little ones from the pouring rain.

"Can she come over to our house, Sans? Please?" His younger brother pleaded and Sans nodded in response. The happy cheer from Papyrus and slight smile on Undyne's face made it worth it.  
As the night progressed with Sans fondly watching Papyrus play with Undyne and share stories, a feeling crept up into his soul. He frowned lightly, confused by the negative emotion.

What was this? Something caused by the Doctor's experiments...?

As the night progressed, Sans realized what the emotion was, but he couldn't for the life of him figure out why he was feeling this way.

He was jealous.

Was he jealous that Papyrus had made a friend? Something that Sans didn't have the luxury or willpower to do?

...Or was he jealous of Undyne for taking his brother's attention from him?

Sans frowned, that was ridiculous of him. He should be happy that Papyrus had made a friend. His younger brother's sadness from not having friends was something that sometimes sent the younger skeleton into tears, something Sans absolutely hated. He didn't want Papyrus to be sad, ever.

He could deal with jealousy. It wasn't his place to deny Papyrus the joy of making new connections. If anything, this would protect the younger monster even more. There would be less of a chance of him noticing that Sans sometimes came home late. That sometimes he would flinch if hugged suddenly without warning.

This...this was a good thing. Sans forced himself to smile but it ebbed into something genuine at the happiness Papyrus was displaying.

This was a good thing.


	3. Chapter 3

\---------------

Current Ages:  
Sans- 14-15  
Papyrus-10-11

\----------------

"Nyeh heh heh! Look, Sans! I have caught up with you!" Papyrus struck a triumphant pose as they both took in the new measurements marked on the front door frame. Sans had only grown four inches in the three year span that they had done this. They were both now four feet, eight inches in height. Melancholy gripped Sans' soul as he realized he most likely would never grow any taller.

After all, the skeleton had permanently damaged his HP. It made sense if his physical growth reflected what he had done as well. He grinned widely at Papyrus' expression though.  
"must be all of that milk you have been drinking, bro." He insisted, expression softening.

"Nyeh! Plenty of milk for strong bones!" The younger skeleton declared with a grin but then he peered closely at Sans, which made nearly unnoticeable bead of sweat to appear on his skull.

"Have you not drank a lot of milk, Sans? You're an adult, shouldn't you be taller?"

It took a moment for the question to make sense. Ah, everyone else thought he was actually twenty two due to him working. Papyrus must have asked someone around town or overheard a conversation. Every monster was so different, so it wasn't like anyone could prove Sans was actually much younger.

"i think this is as tall as i get, pap." Sans murmured softly, "i...didn't drink much milk when i was a babybones."

Papyrus scoffed, "you should have known better, Sans! You taught me how important it was, after all!"

Sans smiled gently and patted his younger brother on the skull. Papyrus almost sounded like a mother hen when he scolded Sans. At least he hadn't noticed anything else besides his short stature.

"you'll probably grow really tall, bro." He told the excited skeleton.

"Like our dad?!" Papyrus exclaimed with a proud grin. Sans forced his face not to give away anything. His brother thought their parents had Fallen Down.

"yeah, just like him." He answered, though his soul trembled at the comparison.

\---------------

Current Ages:  
Sans- 16-17  
Papyrus-12-13

\----------------

Sans' eye sockets opened halfway; his dull white pupils taking in his own room in confusion. He usually had nightmares when he did manage to sleep and he thanked all of the stars that Papyrus was an extremely heavy sleeper. But what had woken him this time..? The skeleton ran the day through his mind with a frown. He had worked his shift at Grillby's after he had dropped Papyrus off for monster school. The visit to the lab had been a hazy cloud of pain as Gaster injected him with more of that mystery fluid.

Finding notes on what the Doctor was doing to him was impossible. He knew the basics of Wing Dings, his father's own language, absolutely everything was written in it. A very smart move for someone who kept a lot of secrets. Sans could only hope that whatever the Royal Scientist was doing that it wasn't big enough for Pap to notice or that it wasn't working at all.

The skeleton shifted on the mattress he had finally purchased for himself. He felt...restless.

His eye sockets opened wider and Sans huffed, trying to get comfortable but failing entirely. What was this? A side effect from the injections?

When his left eye flared with unintentional magic, Sans forced down his panic and shivered, tugging his shirt off in one motion. His inverted teal soul was quivering and he lightly traced the many pocket-holes made by the injections on his hip and thighs.

He inhaled sharply at how sensitive that area was. Gaster had moved to his shoulder blades, which hurt just as much. At least it didn't hurt here anymore...

This...felt really nice. Oh. Sans felt silly then, a small smile pulling at his mouth. This was a sexual thing. Coworkers were really candid with rumors and gossip, so he had overheard enough. It was strange though, the skeleton hadn't really been interested enough to explore himself.

He had no friends or anyone he would even consider pursuing romantically.

Sans just had Papyrus.

Maybe this was a reaction to stress? That was logical, he was exhausted and in pain every day. Seeking relief through orgasm didn't seem strange.

Sans closed his eye sockets all the way and just ran gentle phalanges teasingly over each rib, dipping between them. Tentatively, he fingered his spine and gasped; breathy. 

"Mmm..." That felt so nice. He wrapped his entire hand around the spine and began to stroke up and down. A teal flush covered his cheekbones as Sans worked himself up, only stopping when his soul grew warm and there was a heaviness in his mouth.

Blinking, the skeleton parted his fangs and something bright cyan glowed just within his vision. Bringing his free hand up, Sans lightly touched the new appendage and moaned. Slick ectoplasm coated his sensitive fingers and he pressed them into his mouth, working his tongue against them.

Papyrus...was in the next room... He needed to be more quiet. But that just seemed to spurn Sans on more. His soul warming up again to form something hard underneath his boxers. There was a hint of a glow where something strained against the fabric, the same color as his new tongue.

Sans freed the weeping appendage after letting go of his spine. He knew this was what he would use if he wanted to reproduce. There were slurs for this body part, no matter how they appeared on male monsters to make things work. It was translucent and thick, throbbing with need and the skeleton wrapped his fingers around it, stroking.

"Fuh...huh..." Sans bit his fingers.

This felt better than anything he could recall. Quiet, he reminded himself. Younger brother in the next room and the walls weren't anywhere near soundproof. He pumped his glowing cock, his hips canting forward into the motion. 

Oh stars... Sans was reveling in the pleasure building up, a trail of cyan drool seeping past his bitten fingers. More fluid oozed from the tip and Sans paused to smear it slowly over the head of his cock.

"Uhnn..." What if...what if Papyrus walked in right now? Instead of mortification, Sans was surprised when his soul pulsed stronger, his pace picking up speed. Pap was too innocent... He wouldn't know what Sans was doing...would probably ask him to teach him-ah!

Thick cyan cum spurted from the tip generously and Sans collapsed against the wall, gasping in air and trying to will the glowing blush from his face.

Once he came down from his high, the skeleton's eye sockets widened and he brought a cum strained hand up to his mouth. Did...did he just get off on the thought of his little brother?! No... No, this wasn't right! Sure, Papyrus was the only one that he loved. But Pap was his brother! Jerking off to the thought of the innocent skeleton was wrong, sick.

Sans' magic dissipated, all of the evidence and enjoyment gone from the act. Self loathing reared up in his soul. He was not only useless, but now he was disgusting. If he ever did that again, he would NOT think of Papyrus. Fixing his clothes, Sans stood and traveled the distance that separated his room from his younger brother's.

He cracked the door and peeked in, smiling in relief. Papyrus was fast asleep and smiling in his sleep. Whatever they had as night cast the other in a serene light.

Papyrus was beautiful.

Swearing internally, Sans quietly closed the door and flopped back down on his bed. He gripped the shoulder blade that had new pocket holes in the bone with a hiss, punishing himself for his meandering thoughts.

Sans loved his brother. But he could not love him in that way. He repeated that over and over in his head until their 'nightime' became 'daytime'. And as always, he greeted Papyrus as he normally did.

\---------------

Current Ages:  
Sans- 18-19  
Papyrus-14-15

\----------------

Sans was sitting by Papyrus' race car bed, reading 'the tale of Fluffy Bunny' to his brother, who was now a complete head taller than him. It was endearing that his younger brother still needed a bed time story to get to sleep, even more so that he still selected his favorite tale that Sans had started reading to him when he was a toddler. The book was well loved, nearly falling apart at the bindings.

Papyrus' expression was serene when he glanced up from the book, eye sockets half lidded as the skeleton listened to his older brother read. His nearby table had a collection of action figures that 'Santa' had brought him for Christmas. Sans had never asked for anything for himself, but last year; Papyrus had downright refused to let his older brother get away without a gift.

So, Sans received a light blue winter coat that zipped up the front, with some fluffy fur lining the hood. It added quite a bit of bulk to his figure, but Sans didn't mind. He only took it off when he had to exchange it for a lab coat. That coat was his first and only gift from his precious brother, he wouldn't allow it anywhere near the lab.

He quietly finished the last lines of the tale, "and Fluffy Bunny hopped home again, with all of the help from his new treasured friends." Sans closed the book, careful of the damaged spine before the white pupils in his sockets trained on Papyrus' face.

He smiled softly. Deep asleep; as usual. Even though the other skeleton was about fifteen now; he still had the same enthusiasm for life and a boundless well of belief for others. Papyrus was now set on becoming part of the Royal Guard as Undyne had recently become inducted.

Sans had taken her aside to request that his young brother be given some sort of training, but warned that Papyrus was too innocent for what the Royal Guard really were responsible for. Instead of wrinkling her face at him, Undyne had nodded in agreement; promising to not let Papyrus get too deep in that business.

Undyne was ambitious, the only true friend Papyrus had kept. They had recently met another female monster named Alphys and Sans was careful to steer clear of her as the reptilian monster was also working in the lab as an intern.

Sans stood carefully and shelved the book, gaze resting on his younger brother as a flush of cyan tinted his cheeks. He really was a disgrace. No wonder Doctor Gaster used him as a pin cushion. Lusting after his own brother, holding more than Platonic feelings for Papyrus...

He was sick...but the small skeleton couldn't help it. He hated himself more and more everyday for it, but Papyrus would never know. There...were a lot of things the taller skeleton would never find out about.

Sans' true age.

Their parents.

Why he was tired all of the time.

That he really didn't work at the lab as an employee...

Why his fluid gait had become a shamble...his entire left hip weak from injection holes that had worn the bone down...

None of his pain.

And nothing of his true feelings.

It was better this way. Papyrus was kept happy and away from the cruel nature of the Underground. Sans would always protect and care for his young bro...like he had promised all of those years ago.

He smiled, a single teal tear escaping as Sans quietly shut the door.

Sans had done a good job...hadn't he? Even if he didn't deserve any of the happiness that being with Papyrus afforded him.


	4. Chapter 4

\---------------

Current Ages:  
Sans- 20-21  
Papyrus-16-17

\----------------

"undyne...i need you to stay with papyrus tonight," Sans whispered into his cell phone in a hushed voice. He had entered Gaster's office as usual, but the new equipment and the sheer number of injections laid out told the skeleton that going home that night would be impossible or just a very bad idea.

Gaster...wouldn't really kill him, would he? He sweated nervously, white pupils flicking over to the door. No one had noticed that he had arrived yet.

The monster was cold...but he wouldn't really kill a family member, right?

"Ugh, really?! I had wanted to marathon anime with Alphys!" The aquatic monster complained. Sans took a deep, stabilizing breath. Good, their friend wasn't here.

"why don't both you and alphys have a sleep over with my bro?" His voice shook unintentionally and there was a pause over the line.

"I know you aren't like...my pal and such...and I hate your puns...but you okay, nerd?" Undyne questioned lowly. The skeleton trembled and forced his voice to be steady.

"just tired, i have to work through the night and would really appreciate if you could keep him company."

Please, please, just...say yes. He pleaded in his soul.

"Sure! Pap is a great friend, we'll have 'em stay over." The younger woman stated brashly and the teeth Sans had set in a grimace turned upwards briefly.

"thanks, undyne." He murmured before flipping the phone shut. Taking a moment to allow his left leg some rest, Sans managed to enter the office without a noticeable limp. Gaster eyed him coldly above his glasses and motioned over to a table with restraints.

"Lay down." Was the curt order and Sans obeyed without question, though he was clearly afraid. The skeleton had tried to be tough in the beginning. Tried not to scream. But it was just too painful. Gaster seemed less vicious if he vocalized his agony in any case... The Royal Scientist strode to him with grace, Sans flinching as the straps were quickly snapped and buckled down, digging into his sensitive bones.

"Now...we are going to take as long as we need tonight, no begging or excuses. If I don't get a result from you, I will move on to your brother."

Sans' pupils dilated with fear and he gasped, "no, no, please....not pap...please..."

"Then be useful for once!" Gaster's long phalanges dug painfully into his shoulder and Sans shuddered in fear.

"anything...anything...please..." The skeleton was suddenly out of his mind with fear, his left socket flaring cyan, flickering between blue and yellow in a panic. But...what was he supposed to do?! Dr. Gaster never told him what these experiments were for!

The first painful injection dug into his lame side and Sans screamed, fangs parting in agony as he wailed. A dozen injections later and he was losing his grip on reality, his brother's name running through his mind as a prayer over and over.

Please... Whatever Gaster wanted from him...Please...

The Royal Scientist's disappointed frown burned into his skull. Had...had they been through all of the injections already...? How long had it been?! Papyrus! No! He couldn't let his brother be taken!!

Dr. Gaster inhaled sharply as Sans' body vibrated, creating a triple image before the young, tormented monster had messily teleported across the room, far away from him. The younger skeleton gripped his skull, screaming in pain as his form phased in and out of existence. On one side was Dr. Gaster and the lab. On the other...

Was nothing...

Absolutely nothing.

Sans was frightened of it and thrashed against the wall as Gaster took a cautious step forward.

"Fascinating..." The Doctor breathed and teary eyes raised to look up at the towering form, his body unsure where it wanted to be.

But that one word had been the only time his father had ever praised him.

"You appear to be teleporting, tell me; what do you see in between?" He was all business now but Sans felt like his soul was being torn in two. Like he might 'teleport' and leave some of himself behind.

It hurt...ithurtihurtithurt!

"Progress at last. At least I won't have to start from scratch with the other one." Was the derisive tone the Doctor spoke in, but Sans couldn't help but be relieved.

Papyrus was safe...

Gaster wouldn't touch him...

Nothing else mattered.

\---------------

Current Ages:  
Sans- 22-23  
Papyrus-18-19  
CORE INCIDENT

\----------------

It was a normal morning. Well...as normal as life got for Sans. On the surface, it was routine. Sans fixed something for breakfast before his younger brother would run off for training. His favorite at the moment was pancakes. Papyrus had always praised his older brother on his pancakes. When the skeleton had been younger, he had even made them into interesting shapes. Though, the taller brother was talking excitedly about how he wanted to learn how to fix spaghetti from Undyne. His new big favorite food apparently.

"JUST YOU WAIT, BROTHER! I WILL BE THE BEST ROYAL GUARD THE KING HAS EVER SEEN!" Papyrus shouted happily. Sans smiled despite the volume and sat down at the table to eat the fluffy cakes drenched with syrup with his precious sibling. While his younger brother ate happily, the small monster allowed himself to stare out the window as he sunk into thought.

Something...felt off today? It was a strange feeling. Like invisible magic being wrung tightly in the air, threatening to snap. Life had never been more painful than it was now for Sans. His life had always been pain and he had always been useless.

Until now. Sans absently rubbed his left leg while keeping his face blank to ease the pain there. Teleporting had become easier, but Gaster had forced something else into him. It had changed something, just not anything visible to Sans...

Doctor Gaster seemed happy though... So he must be showing results.

"SANS! I AM OFF TO UNDYNE'S!" Papyrus declared and stood proudly. Sans did as well, though he only came up to his little brother's hip at most. He glanced fondly at the 6 feet, 7 inches marked off on the door.

Something gripped Sans soul as soon as Papyrus moved to take off.

"wait!" He reached out and froze. Sans rarely let himself touch Papyrus due to his indecent thoughts. He didn't deserve that privilege, not when he was so disgusting. The taller skeleton turned around and gazed down at his older brother.

The uncertain expression there was not something Papyrus had ever seen on Sans.

But it was gone before Papyrus could comment, the small skeleton shaking his head and smiling.

"n-never-mind. i forgot. i'm a numbskull..." Sans murmured and Papyrus wailed at the awful pun before glancing once more at Sans.

"That was awful, Sans..." Papyrus muttered.

"i know."

"Well....goodbye, brother." Papyrus said in a softer but more decisive tone, tromping off through the snow confidently. Sans stared after his retreating form uncertainly before closing the door and teleporting to the job that now replaced Grillby's.

He was a sentry, as much as he hated it. Sans patrolled near the Ruins but had taken it so that he might encounter Papyrus or on the off chance, actually stop a harmful human. He was only a 1 HP monster, so he would probably only stall them...

But...

Heh...

What was wrong with him today?

A solid five hours went by as the small skeleton took time covering the area, sitting at his station to sooth his now pronounced limp, left leg nearly dragging in the snow. It was like Gaster wanted him lame.

Sighing, he teleported directly to the lab from the sentry station and stepped back in shock as he tugged his lab coat on. Monsters were rushing around urgently and he had to check in with the human resources monster to figure out that Dr. Gaster took a team of monsters and a machine to the CORE.

"what does the machine do?" He questioned and she frowned.

"I...I am actually not sure. The Doctor is probably unveiling it today." Not waiting for a reply, Sans ducked into an empty room and teleported to the CORE, spotting the group of monsters on the walkway to the far right. Traversing the area with a wince, Sans drew near enough to hear his father speaking.

Sans listened quietly, drawing ever nearer despite a warning glance from the Royal Scientist. This...this machine...was supposed to travel through time? No... No, this wasn't right!  
Something felt horribly wrong!

"Gaster, no!" He cried, disrupting the conference and earning a withering look from his father, "you can't do this, you'll create a paradox in time and space!" He pleaded. Gaster glared at him.

"According to my theory, traveling back to the time before the barrier was erected would be harmless, granted that everything I do is within probable physics. And since I am traveling backwards, what I do will just have always been. History changed, except in our favor." The doctor's level tone was bored.

"Human and Monster magic hasn't been studied enough! They might not even be a reliable point of reference for acceptable physics. If you go back and change things, this universe might branch into it's own separate time-line! Where would that leave us?" Sans questioned, limping slightly through the crowd. Drawing closer even though his instincts wanted him to cower from this monster.

Gaster scoffed, "nothing you can say hasn't been argued a million times over. If this time-line is doomed to entrapment, then I will travel to the time-line with the best outcome for myself."

That statement was so selfish that Sans was frozen in place for the few precious seconds that it took for Gaster to turn the machine on.

That wave of intangible magic Sans had been sensing all day finally snapped and he attempted to push past his father to turn the machine off. The smaller skeleton was shoved and both of them careened off of their respective sides of the walkway, down towards the CORE. Sans teleported as a shockwave pulsed from the machine and gasped, hitting the emergency stop lever desperately. He threw himself over to the side Gaster had fallen over to attempt to help him, but...

Gaster was gone...

He shuddered and looked at the walkway. All of the monsters that had been standing here had simply vanished.

What...what had happened?

He teleported, exhausting himself by how flippantly he had used his new ability and everyone in the lab proper was simply...gone.

Papyrus!

Sans teleported once more to Snowdin, so very relieved that there were monsters milling about. He approached the bunny mother he knew from Papyrus attending monster school with her child.

"do you know where papyrus is?" He questioned, out of breath and sweating. The monster gave him a look that was a cross between confusion and concern.

"Papyrus? I am sorry, but do I know you?"

Sans froze, feeling his left leg finally giving out on him. She...but she had known him for years.

Did no one remember?

He weakly limped about town and it all was the same. Confusion. They saw him as a stranger and did not remember anything about Sans nor his brother. Yanking out his cell phone, he dialed Undyne's number in a panic.

"Hello?" The Royal Guards-woman drawled lazily.

"u-undyne. is my brother with you?" Sans asked in a frightened tone.

There was a long pause. Too long. Like something was settling into place.

"Yeah, Sans. I am teaching him how to make...I mean, I am training him!" Relief came crashing in.

"can i talk to him really quick?" He questioned. There was a rustling and muttering noise before...

"BROTHER!"

Sans choked out a sob.

"Sans?" Papyrus sounded concerned now.

"it's...nothing, bro. do," he swallowed, "do you remember what we had for breakfast this morning?"

"OF COURSE I-...actually..." Papyrus made an unsure noise, "that's odd. The Great Papyrus has an impeccable memory! It seems to have slipped my mind!"

"do you remember where i got my blue jacket?" Sans whispered, teal tears collecting in his eye sockets.

"Hmmm....is it important?" Papyrus questioned, sounding confused. The small skeleton made a soft noise.

"no, pap...it's not important. don't worry about it. make sure...to come home safely...okay?" Sans questioned.

"SURE THING, BROTHER!" Papyrus promised before hanging up. Sans listened to the dead line for a complete minute before hanging up.

No one remembered anything before the blast. Sans should feel happy. If he had slipped up at all...at anytime...Papyrus wouldn't remember.

It was like they had suddenly shown up at Snowdin to everyone here.

No one could remember...but why did he?


	5. Chapter 5

**Summary for the Chapter:**

> All new content from here. <3 Enjoy~

Two Months later…

——————————————-

To say that Sans was at the end of his patience would be an understatement, which said a lot about the current situation seeing as his primary personality trait was just that. It had been a few months since the Core Incident, in linear time. 

It was ridiculous that he had to keep track of two different waves of time now. 

The small skeleton frowned at the machine that had caused all of this, eye sockets dark and narrow. He rubbed his left hip idly, lost in thought once more.

No one remembered Gaster. In any capacity. Even mentioning his name had a distressing effect, so Sans had stopped even speaking it. Monsterkind knew someone had invented the Core and had been the previous Royal Scientist, but when asked they would get this oddly vacant look about them before questioning what they had been talking about. It was like he had never existed in the first place. 

At least, to anyone but Sans…

When Alphys had been appointed the new Royal Scientist; Sans hadn’t bothered sticking around. In fact, no one but Alphys seemed keen on continuing in the labs and working.

That had been a few months ago, linearly.

Non-linearly; Sans was stuck in a weird temporal loop of sorts. The small skeleton hadn’t noticed it at first, too caught up in taking care of Papyrus and investigating the aftermath of Gaster’s failed experiment. A few seconds of time stuttering back, snow ascending rather than falling, losing his place in a conversation that was repeated.

It was another thing Sans was alone in. No one else noticed these strange things. It had been a minor annoyance at first but then the instances lengthened before jumping back days. The monster kept meticulous notes on all of the changes in his lab as it didn't seem to be affected by the fluctuations in time. It had just been an inconvenience, especially when Sans was working on fixing the machine.

But then one day, he had found the culprit. And on that same day…

“BROTHER….! P-PLEASE….H-HELP!”

Thick, thorny vines snapping through pristine white bone…

That time… That ‘reset’. It had broken something in him. Never before had Sans experienced such hatred. But that creature… Flowey. It had hurt Papyrus. Killing Intent had consumed his soul as his precious sibling begged him for help and… He had killed the flower. Then the flower killed him. And then he did and so on. And so forth… It had become a game for the deranged creature. 

And they ‘played’. For what felt like forever. Until Sans’ knew the steps by heart. Until he was excessively expert at fighting despite his low hope. Until…the flower got bored of him. Flowey got bored. Of murdering Papyrus. Of fighting him.

Sans should be happy…

But instead, this awful apathy and nihilism had shadowed his soul. Nothing mattered when someone had sway over the natural progression of time. The small skeleton had stopped putting any effort in his physical appearance. He stopped cooking for his younger brother until it was a rare occurrence. He stopped masking his lame left hip, his limp through the snow bordering on painful. Just so that he could feel something…

Sans stopped eating for the most part. Only popping ketchup packets on occasion. His grin was fixed, his clothes stained and messy. Jokes were a go-to distraction if his brother began to question him too much. Dear stars… Papyrus. His brother was so worried.

The skeleton had woken yesterday and had a terrible thought... 

What if these resets took away his ability to love Papyrus? 

So, Sans had thrown himself into working on the machine without any breaks. Until he collapsed only to wake again to work even more. He couldn’t stop when Flowey may reset and undo all of his progress. He needed to do this. For his brother. For his sanity.

And… it looked like everything was where it belonged. His narrowed eye sockets moved along the inside of the machine, along the circuitry and wires critically. Nothing was missing. But then, when the skeleton had salvaged the machine, it had looked similar. All Sans had were theories and some blue prints written in Wing Dings. He was far from fluent in it but…

All of the inner workings appeared to be ready.

The small monster trembled, shaky phalanges hesitating.

Papyrus was at Undyne’s, so the shock-wave that the machine had expelled wouldn’t hurt anyone nearby like it had with the monsters in the lab. The closest anyone would be at this hour was Grillby’s and that was too far for the machine to harm anyone.

…He was stalling.

Sans shut the panel and his dim eye-lights flickered over the display. He had done all he could. It this went wrong…no one would remember him, just like Gaster. He shouldn’t care. He shouldn’t be afraid. Not when so many of his emotions had been killed over the course of so many resets.

But he did care. 

If this worked, Papyrus would be safe. There would be no more resets. Linear time only.

Sans had noticed that his younger brother had nightmares. Just like him… This had to stop. 

In theory, one press of this button would nullify the damage done to the fabric of time by Gaster.

Sans could go back to how things had been, without the threat of their father hurting Papyrus hanging over his head. There wouldn’t even be anymore experiments done everyday to hurt him. Time would flow as it should and everything would be okay.

The small skeleton inhaled sharply and closed his sockets tight, a pang of terror pulsing in his rib-cage before…

Sans pressed the button.

—————————————————————————————————————

Papyrus frowned as his cell rang until it hit the automated message Sans had set. He hadn’t thought much about it, at first. It was more often than not that his older brother would be napping. But he had called three separate times, all spaced out over the day.

Sans still hadn’t picked up…

Worry had settled in the tall skeleton’s soul, even as Undyne continued whole-heartedly through their lesson. Something was wrong, he knew it. Something had been wrong for a very long time. In these past couple of months, Sans had been excessively troubled. Papyrus couldn’t remember much but his older brother had always taken excellent care of him and he had taken care of himself. While it was still obvious that Sans loved him, it seemed like all life had been drained from his brother. He was great at many things, but stealth was a weak point. Checking Sans outright seemed like a horrible breach of privacy as well.

Something was terribly amiss with his older brother…

“UNDYNE! I MUST HEAD HOME NOW!” He insisted after the fifth failed call.

Something was wrong!

“Eh?!” His best friend looked up from the anime Alphys had let them borrow, “but it’s still early!”

“NO, I AM SORRY, BUT I REALLY MUST GET HOME NOW!” He was already up and wringing his gloved hands together. Something was wrong…something was wrong! Undyne blinked her good eye before frowning at him.

“Okay, nerd… You call me, got it?” She questioned in a softer tone and Papyrus nodded as he rushed out the door. He usually was a stickler for jogging all the way back to Snowdin as exercise but the skeleton dashed the other way towards the Riverperson. 

“TAKE ME HOME!” Papyrus requested breathlessly, “TAKE ME TO SNOWDIN.”

The Riverperson tilted their hooded head at him before humming thoughtfully, “long overdue journey today, isn’t it?”

Papyrus was silent, confused at the declaration before the boat suddenly was moving. The humid air quickly became chilly as they made excellent time. When the boat stopped, the younger brother murmured a quick ‘thank you’ before he was running full tilt towards the town.

“SANS!?” He called as he stomped the snow from his boots, entering their home to find all of the lights shut off. The skeleton frowned in response.

Perhaps Grillby’s?

He shut the door to their house and took off down the main road. 

Sans wasn’t in the bar. 

W-Was his lazy sibling actually working?

A trek to Sans’ sentry station came up just as empty. Papyrus was glad he hadn’t run from Waterfall; this was a workout in and of itself. The feeling that something terrible happened hadn’t faded, only growing worse.

Papyrus hesitated and took the route home much slower. 

If Sans wasn’t working, wasn’t at Grillby’s bar and wasn’t home…where…?

He stilled and frowned at the gentle flurry of snow falling from what magic controlled the weather in this region. The younger sibling faintly recalled coming across a silver key more than once while cleaning Sans’ room. He had pretended that he hadn’t noticed it.

Just as much as he pretended not to know of the locked door behind their house.

Papyrus lived there, of course he would notice a suspiciously locked door! …Was Sans in there? Why hadn’t his brother come out yet? It was getting late…

He hesitated outside the front door once he got back to their home. The lights were still off… Sans would be mad at him if he snooped, wouldn’t he? His brother had always seemed to like his privacy.

But what if something had happened…?

Papyrus wouldn’t forgive himself if Sans was hurt and calling for help back there when he knew the option was there. Steeling his resolve; the tall skeleton rounded the house; long red scarf trailing behind him. 

…The door was ajar.

Sans kept this door secret and locked at all times. Soul sinking, Papyrus pushed open the door and went down two flights of stairs to discover artificial light filling a small room. All details and interest in finally seeing the secret room vanished the instant he saw-

“SANS!?!”

Papyrus rushed across the room and knelt by the prone form of his older brother, gingerly pulling the smaller skeleton into his arms. He patted Sans’ cheek, but his sibling didn’t stir. His eye-lights shot up to discover the cracks in the adjacent wall where Sans must’ve been thrown back… The blackened husk of some sort of machine was still smoking slightly; the insides just as charred as the front of Sans’ shirt and…lab coat?

He didn’t understand… His brother had never worked in the labs...

His attention snapped back down to his older brother, trying to rouse him gently but Sans wouldn’t wake. No matter how loud Papyrus shouted or how much he was jostled.

Was this what monsters looked like when…when they Fell Down?

Papyrus ‘checked’ Sans, politeness and privacy be damned. This was his brother!

Sans

LV: 1  
HP: 1  
AT: 1  
DF: 1

*He loves you.

….What?! This couldn’t be right! Ignoring the simple description that made his soul ache, this just couldn’t be Sans’ stats! But they were there, right in front of him, clear as day and undeniable. M-Maybe all monsters had that low of Hope when they…

No! Sans couldn’t be Falling, he refused to believe in it!

“DO NOT WORRY, BROTHER!” He gently gathered Sans’ tiny body into his embrace, “WE WILL TAKE YOU TO DOCTOR ALPHYS. SHE WILL…KNOW WHAT TO DO!”


	6. Chapter 6

**Summary for the Chapter:**

> Hello~ I am back from the holidays! <3 For those that don't follow my Tumblr, I announced that this story will be completed this month with a total of 16 chapters! I will then take On The Other Side off hiatus and work on Karmic Retribution as well! They won't be getting any new chapters until this one is done!
> 
> For more news and just updates/behind the scenes things; please follow my blog!
> 
> NSFW- mercy-run.tumblr.com

Papyrus was certain that he had never traveled so quickly from Snowdin to Hotland, nor been so rude to the Riverperson. Thankfully, the ferry-monster hadn’t seemed to mind his haste and made the trip without complaint. Perhaps that was due to the still body of his older brother clutched to him, but the skeleton was grateful that they ignored his less than tactful language nonetheless. He hurried to the lab and pounded on Alphys’ door until to his utter shock; Undyne opened the door. The was a single moment in which both of them seemed frozen from surprise before her single yellow eye lowered to find Sans, widening in a naked display of horror.

That didn’t help the taller skeleton’s state at all; orange magic finally spilling from his sockets. Had his optimism been misplaced? Was his brother really…?

“U-Undyne…” Her gaze jerked back up to his face at the tremor in his voice, his normally loud tone nearly a whisper. That combined with the hopeless expression his face was falling into snapped the Captain into action. The aquatic monster slapped a hand against Papyrus’ shoulder and ushered him inside; the metal door ‘whooshing’ closed behind them.

“ALPHYS!” She called and the small yellow scientist peeked over the railing of the second level, her gasp nearly swallowed by the volume of the television behind her. Papyrus wondered distantly if he would have been hurt that Alphys and Undyne had continued the anime they had been watching without him if things had been different as she hurried down the conveyor.

“I-Is that S-Sans?!” The Royal Scientist demanded shakily, coming to a halt a foot away from them, looking over the slight charring on the skeleton monster’s ruined lab coat, “w-what happened?!”

Both of their attention fixed on him and the skeleton monster felt a brief flash of panic well in his soul. He didn’t know exactly what had happened! His older brother hadn’t even spoken about that room before!

“I am not sure!?” He choked out, voice rising steadily in his distress, “he has this secret room in the basement and I didn’t know what he was doing but I FOUND HIM DOWN THERE LIKE THIS! THERE WAS AN ODD MACHINE THAT LOOKED LIKE IT HAD BEEN SET ON FIRE AND HE WASN’T MOVING NO MATTER HOW MUCH I SHOOK HIM AND-”

“Pap!” Undyne attempted to placate him but now that he was speaking, all of his emotions were just bursting forth.

“HE ALWAYS HAS BEEN SECRETIVE! I TOLD HIM YOU WOULD HELP HIM, EVEN THOUGH HE PROBABLY CANNOT HEAR ME!” Papyrus sucked in a shaky inhale, tears streaming freely down his face as he asked what had been repeating in the back of his mind, “ IS-IS HE FALLING DOWN?”

Both of his friends appeared shell-shocked from his outburst but Alphys quickly rearranged her glasses and reached out to take one of Sans’ limp hands. The younger brother resisted the silly urge to pull his sibling away from her touch. She was a doctor, she would help Sans and to do that she would need to touch him. The secondary effect from standing so close to a ‘check’ rippled through both him and Undyne; drawing sympathetic magic from them both.

“His hope is… Has it always been like that?”

He blinked his eye sockets at Alphys suddenly firm and serious tone; not a single stutter tripping her words as the Royal Scientist lifted one crispy flap away from Sans’ wrist.

“I DO NOT KNOW.”

“You said this damage came from a machine?” She questioned.

“YES! I DO NOT KNOW WHAT IT WAS FOR BUT IT WAS SMOKING LAST I SAW.”

Alphys frowned as she released the limp hand and motioned for them to follow. She pulled something out from underneath a bunch of empty instant noodle containers and papers. Papyrus winced at the mess but focused on the tablet she had pulled free.

“Lay him down, I can scan his s-soul with this.”

Relieved to actually have something to do instead of being hopelessly lost, Papyrus gingerly lowered his older brother onto the floor and carefully arranged his arms alongside his small body. Under the bright light of the labs, the younger skeleton realized that most of the damage seemed to be superficial. The charring was only on his clothing but his bones were blackened from soot, not actually burned black. Alphys held the device over his brother’s chest and it’s monitor displayed ‘scanning in progress…’ before a bunch of information filled the screen. Sans’ stats… A bunch of numbers and words that meant next to nothing before his attention went to a bold line of glowing text.

Soul condition: STABLE.

Papyrus wanted to shout with joy but doubt instantly followed. If Sans’ soul was alright then…

“Why isn’t my brother waking up?” He asked quietly. Alphys frowned at him before rechecking the screen. Apparently that didn’t provide an answer because her gaze returned to his face, slightly nervous now.

“I-I don’t know why he is still un-unconscious. The readings say his soul is perfectly fine despite t-the low stats.” The Royal Scientist’s out-of-character composure from before was gone, “but he is unresponsive. H-He may have just o-over-worked himself?”

That was less than reassuring. Papyrus could have sworn there was a time that his brother often “overworked” himself but perhaps that had been a dream? The lazy demeanor Sans had been displaying these last few months seemed more common, more real.

“Sans didn’t tell you what he was working on?”

Undyne’s words recaptured Papyrus’ meandering attention and he frowned. He was very quickly tiring of not having information on Sans. His only family. The most important monster in the Underground to him. Though it had seemed his time was mostly spent with Undyne, his brother had this unquestionably firm and permanent place as coming first in his soul.

Why did he know so little when as his only family, Papyrus should be the leading expert on everything about his older brother?

“I DID NOT KNOW ABOUT WHAT WENT ON IN THAT ROOM. DID SANS USED TO WORK WITH YOU?”

It was Alphys turn to appear abashed.

“N-No? I can’t remember a-anytime where Sans even expressed i-interest in science.”

This was ridiculous. Even the Royal Scientist, who seemed to be the only one in the know about anything about what Sans would’ve been doing, had no idea. It was…disheartening. Confusing. It just didn’t make sense. Even if Papyrus had been paying zero attention to his older brother, something should have tipped him off. Right…??

A gentle touch at his elbow had Papyrus jerking his attention back to both women.

“D-Do you want me to k-keep Sans under observation?”

His gaze snapped down to his older brother laying on the floor, a fierce sensation of protectiveness pulsing through his soul. 

“NO. I WILL TAKE MY BROTHER BACK HOME.” He insisted, gathering his sibling up into his arms quickly but carefully; as if they might try to keep Sans here without his consent, “HE WILL BE MUCH MORE COMFORTABLE THERE!”

Undyne and Alphys exchanged a worried look but they didn’t move to take his brother from him, “you will tell us if anything changes, right?” Undyne questioned, to which he nodded. 

“I WILL.” Papyrus promised.

“D-Don’t hesitate to bring h-him back?” Alphys told him, the offer sounding more like an inquiry than an offer in her nervousness. The tall skeleton nodded, cradling Sans’ skull as he made his promises; suddenly feeling silly. He came here without any helpful information. If Sans had been Falling, he wouldn’t have been able to give any useful information. Thank the stars his sibling was actually okay…

Well, as okay as possible in this situation…

Papyrus exited the lab with Sans in his arms, opting to walk the entire way home. He needed time to think and the skeleton honestly didn’t want to face the Riverperson so soon after his…overreaction? The heat of Hotland ebbed into the cooler but more humid setting of Waterfall as he got lost in his mind. Things…hadn’t been ‘right’, lately. The younger brother couldn’t pin down where this feeling came from, nor what caused it. His memory was usually sharp and impeccable but lately it was like his thoughts were scattered. Along with unusual bouts of deja-vu and nightmares, something also seemed to be very wrong with Sans. But whenever he attempted to focus on it, his skull began to hurt something terrible and his soul would begin fluttering in distress.

So he had left it alone.

Now, Papyrus wondered if ignoring something so clearly important had inadvertently harmed his sibling. He had known something was wrong with Sans. But he hadn’t pushed. Now that his older brother was unconscious with stats that were terribly low, he couldn’t help but blame himself for his oversight. The tall monster had thought he was being courteous. That Sans would come to him if something truly was amiss. But Sans hadn’t and he hadn’t pushed and now look where they were…

His sockets lowered to Sans face and resolve claimed his expression.

Papyrus would find out what had happened to his dear older brother. Even if it caused nightmares and headaches. Even if it was distressing. Sans was just too important to him to do nothing in response to his current condition. The rain gave way to drifting snow and the skeleton glanced down at Sans’ face, finding it lax. …More peaceful than he could ever recall.

Snowdin’s denizens kept flashing him worried and curious looks, so the tall skeleton hurried back to their home; shutting and locking the door behind him. The silence of their home was unnerving so Papyrus began filling it with his voice, gently maneuvering Sans until their ribs were pushed together, his arms linked underneath the smaller skeleton’s femurs.

“I WILL BE TAKING CARE OF YOU FOR NOW, BROTHER! YOUR ROOM IS MUCH TOO MESSY SO I HOPE YOU WON’T MIND STAYING IN MINE.” He announced.

Silence answered him.

Sans was so still… It was usually now when he would crack a pun or smile tightly with an accompanying joke.

He ascended the stairs and entered his room. Laying the smaller form of his older brother on his sheets, Papyrus realized that keeping the ruined lab coat on the other skeleton would probably not be wise. A light orange flush touched his cheekbones as the taller skeleton carefully stripped Sans of the ruined clothing. His sockets lingered slightly on his sibling’s limp form before regarding the offending garment. It was ruined. Papyrus hoped there was no sentimental value to it because he would be throwing it away. There was simply no saving it.

Balling the charred lab coat up, Papyrus fretted over the problem of the rest of Sans’ clothes. He was absolutely certain he had never seen his older brother nude. Stripping him completely felt embarrassing, even if it was for something like this. Surely the other skeleton would wake up before it became an issue. For now, there was little damage on what his sibling was wearing.

Papyrus tucked Sans in, smiling sadly.

“JUST REST, BROTHER! I WON’T YELL AT YOU THIS TIME.” His expression faltered, “Y-YOU ARE JUST ILL. SICK PEOPLE MUST GET SLEEP. IT IS IMPORTANT.”

No response. 

Sans really looked like he was just sleeping.

Hesitating and merely staring at his brother, Papyrus took a long time before he managed to tear himself away from Sans, getting up to throw the lab coat away. He frowned, sockets narrowing. Now seemed like the perfect opportunity to investigate the secret room…


	7. Chapter 7

**Summary for the Chapter:**

> Part one of tonight's update! There was a time skip, so I am posting them separately. Will be more when I complete it shortly!

Setting foot in the secret room made Papyrus feel both guilty and jumpy. It felt like any moment now his older brother would find out he was snooping where he wasn’t supposed to be and he would get into trouble. It was a shame that wasn’t the case, because the younger sibling wouldn’t be looking down here unless he absolutely needed to be. Sans was in trouble because of an accident that happened down here. Perhaps he should have been a bit more insistent about knowing where Sans was and what he was doing?

Still.. It didn’t help his nerves one bit…

Now that he wasn’t in such a panic, Papyrus paused at the base of the stairs to take the room in. It was a small space. Smaller than even Sans’ room. The machine wasn’t smoking anymore, but it was in ruins. The tiling exactly opposite where his older brother must have been blasted back was crumbling. He touched the wall absently, finding the blue surface to be fragile already; chips clinging to his gloves. His sockets lowered to the floor; discovering the ground littered with papers. Brow scrunching in concentration, the tall monster crouched and picked up the nearest paper.

The entire surface of the paper was covered in Sans’ handwriting.

He would know it from anywhere, seeing as they were always leaving post-it notes for the other to find. Especially concerning the sock in the living room. But the words and numbers here made zero sense to Papyrus. It looked extremely…scientific. Something that you would have to study years for. He was great at puzzles but this was far above his current level of understanding. Trying to decipher this was unrealistic, so the skeleton took a mental step back. The words made no sense, the numbers made no sense, however…

The handwriting here was frenzied, like whatever the subject matter was had been under a strict timer.

Papyrus frowned.

What would Sans look like when he was panicked? Frightened? Even harried?

It was hard to even imagine. His older brother had always been the epitome of ‘laid back’. ‘Devil-may-care’. Even… ‘relaxed’? To picture his older brother fretting over something so much that he decided to use every inch of space on what he was writing on instead of just getting a new piece of paper… The younger brother couldn’t fathom it but the evidence was right here…

Perhaps Alphys could make sense of this?

To have a starting point was a relief… He gathered up all of the papers that looked to be written in the same way off of the floor, setting the stack aside on a counter. With the floor clean, Papyrus frowned at the actual workspace. It was nothing like the Royal Scientist’s. There weren’t any personal touches anywhere apparent. No ketchup packets. Not even a garbage can. This area wasn’t ‘lived in’, strictly feeling like it was meant only for work.

A spark of worry fluttered in his soul. That was so…unlike what he knew of Sans.

Next, he inspected the actual area of the accident. The machine was useless and Papyrus couldn’t discern what it had been meant for. All that was left of it was charred tubing and metal. If some of this had been circuitry, it was now far beyond repairing. His gaze wandered back to where Sans broke the tiling from where he had been blown back. There was some shrapnel and debris, but none of it could have struck his brother. The wall crumbled at his touch and suddenly, the skeleton found it hard to breathe.

Oh stars…

Sans’ stats had shown one measly shred of hope. Only 1 HP.

Papyrus brought a shaky gloved hand up to his teeth in horror. 1 Hp. Only one. How had this accident not killed his brother? Had close had he come to finding only d-

The skeleton sank to the floor, the rattling of his bones only registering once his breathing had evened out enough. Had Sans known how dangerous what he was working on was? Surely his older brother would know about his fragile health and take precautions…right???

…Or…

A lot of things today were proving to Papyrus that he knew very little, if anything at all about his brother. And that hurt in a very excruciatingly personal way. Had Sans maybe done this knowing the dangers and simply…not care? Wouldn’t that mean that he didn’t care about leaving him alone? That he didn’t care about him?

No. His soul rebelled against every thing about that last thought.

Sans loved him. That was the ONLY thing Papyrus was certain of. If not through Sans’ own actions but through the simple fact that his checked stats had told him so. ‘He loves you’. That was what it had told him. Deciding to continue now that he was suitably calmed down; the monster reached over and pulled open one of the three drawers in the cabinet. Fully expecting not to understand what he found, Papyrus’ soul leapt when he recognized the string of words instead of finding science jargon.

**‘*located the anomaly today. 1 day - 3 hours -52 minutes - 29 seconds-’**

Papyrus frowned and glanced ahead. There were so many time stamps… One for every line.

**‘*anomaly killed paps. 41 minutes - 11 seconds-’**

What WAS this? There was no doubt in his mind that Sans was referring to him. That was his nickname. But he was clearly alive…

**‘*it killed me. 5 seconds.’**

**‘*it killed me. 10 seconds.’**

**‘*it killed me. watch out for the attack from behind. 30 seconds.’**

This continued. Page after page with the following time increasing into minutes until…

**‘*i killed the anomaly. 14 minutes.’**

None of this made any sense! This was just as bad as the papers with scientific formula! Him being killed by this ‘anomaly’. Sans killing anything or anyone! This…! This… This was just frustrating him. He stacked all of the papers neatly and put it in a pile next to the other one, resolving to let Alphys read them. Certainly the scientist could glean more from them than him. He slowly ran his gloved hand down his face and sighed. Papyrus wasn’t used to feeling panicked. Or confused. Or afraid.

But he was feeling all of those things now.

And what was bothering him most? It seemed…like Sans was a stranger. Was everything he knew, besides Sans loving him, a lie? How long had his older brother been lying to him? And why?

Standing utterly still for a few moments, Papyrus searched his feelings. Yes, he was shocked and hurt over all of these secrets. But… He wasn’t mad. He believed in his older brother, despite the secrets. Sans was a good person. The most important person, who obviously loved him! Papyrus loved him too! Sans was his only family. He could place his hurt and shock aside until it could be fully addressed. For now…

Papyrus would take care of his older brother.


	8. Chapter 8

**Summary for the Chapter:**

> Aaand the second part of tonight's update. <3 I hope there aren't too many typos.

A few days had passed since Papyrus had found Sans unconscious in the secret room underneath their house. The taller skeleton had been dearly hoping his older brother would have woken up by now, but there was no improvement and no change. The skeleton normally didn’t sleep, especially not without his bedtime story of Fluffy Bunny; but he was actually starting to feel fatigued. He had made more trips to the lab in Hotland than he cared to admit but Alphys would scan Sans, never having any good news.

He had been sleeping on the floor next to the bed with his smaller brother tucked in, holding onto this childish hope that Sans would wake up before he would have to breach anymore boundaries than Papyrus already had. The secret lab basement thing was one matter. But Sans really was in need of a bath and a change of clothes. He was still in the slightly damaged shirt and shorts of two days ago.

A faint orange glow touched Papyrus’ cheekbones as he stared down at Sans laying prone on his bed.

He had never seen his older brother naked before. Even with the dubious information he had been sitting on (and not gave to Alphys despite having the opportunity), he was one hundred percent certain of that, at least. It was a clear, unspoken boundary! Probably one all siblings had. But by his personal standards, Papyrus didn’t want his sibling’s hygiene to suffer just because he was embarrassed!

“Sans…” The tall skeleton questioned, his voice lower than usual, “can you hear me?”

It was something he asked multiple times a day, to no avail. But talking to Sans helped some…especially when the house was so quiet. His brother lay still, like he was asleep.

“I have to give you a bath, brother.” Papyrus tried, hoping maybe just perhaps mentioning something along these lines would spark some movement. Sans didn’t move and he frowned, resigning himself to trespass on yet another of his sibling’s boundaries. He had long since swapped his battle body for an orange sweater and gray slacks, his hands feeling odd without the gloves.

“I’ll be careful.” The taller skeleton promised as he gingerly eased the bedding off of Sans’ small body. Was it just him, or did the smaller skeleton seem even…tinier than usual? Perhaps it was the absence of that bulky blue coat Sans seemed dead-set on wearing everyday? Shrugging the oddity off, Papyrus easily picked up his brother and made his way to their bathroom.

He could do this… Why was he so nervous, anyway? Sans was helpless right now and needed his assistance. It was just bones, after all…

Just…bare…bones…

Papyrus felt like his magic was burning a permanent blush on his skull by the time he shut the door behind them, locking it for good measure. His hold on Sans tightened just barely at the sight of the bathtub. Really… What was the big deal? He was doing this to take care of Sans, there was nothing ‘scandalous’ about it.

“We’re in the bathroom, now;” he announced, unnecessarily.

Sans was just as still and quiet as ever.

Papyrus frowned. What was it that was bugging him? It couldn’t just be that he was about to see his sibling naked, right? …Maybe he was scared that when Sans found out he would be angry with him? But that was silly, wasn’t it? Sans would understand. He really would.

Huffing an exasperated breath, he closed the distance to the tub and sat down. He needed to stop acting like a babybones! Sans was sick! He couldn’t care for himself in this state. There was no shame in this…

He hesitated, wondering if Sans preferred warm, hot, cold or cool water… Being a skeleton monster was deceptive as they could feel the temperature just as well as any other monster. It just took longer for them to achieve the adverse effects. Papyrus glanced down at his sibling with a soft frown.

“Well, you are always wearing that coat so…perhaps…” He murmured to himself before reaching into the tub, stopping it and twisting the knob to a warm temperature. The monster watched as it began to fill and sighed. Okay, enough being a babybones. Papyrus was going to step up and do his best to take care of Sans, like he had decided.

Still flushed a deep orange, the taller skeleton hooked his phalanges under Sans’ shirt and lifted it free of the other’s arms and spine, careful not to jar anything. The first thing that registered was how narrow Sans’ bare rib cage was in comparison to his. The next had him leaning forward, confusion knitting his brow.

What…what were all these…?

While Sans’ rib cage was smooth and pristine; there were odd pocket-marks, holes and visible scarring all along his shoulders and lower spine.

“What…?” Confusion echoed endlessly throughout his soul at how concentrated these markings were. Some looked very, very old. Others looked to not even have been made half a year ago. They were concentrated… 

Deliberate.

Embarrassment forgotten in Papyrus’ growing horror, he pulled off Sans’ socks and then lowered the last garment down his small legs.

He couldn’t even focus on what he had been agonizing over on the way from his room to the bathroom. It didn’t matter that he was seeing his brother naked, now. Not anymore.

“Oh stars…” Papyrus whispered, sockets trained on his older brother’s left hip. It was like a war zone. Like some needle-fanged creature had chewed away at the bone here until there was barely anything but magic holding the two limbs together. Papyrus wasn’t sure what to think. What to feel. Disbelief. Doubt. Sympathy. Confusion. Anger. It was like his being wanted to go through the whole spectrum of emotions at his discovery. Secret basement lab was one thing but all of these wounds…

Had someone been hurting Sans?

Had he been perhaps…doing this to HIMSELF??

The younger brother had noticed Sans had a limp. But he never thought to question it. Sans had never let on that he was in pain. But the secrets were just piling up. The questions even more so. Papyrus wanted to scream and shake his brother until his sockets opened. He wanted to cry and hold Sans close. Ask why? Ask how? 

Had he failed as a brother for not noticing?

…The water spilling over the lip of the tub had the skeleton scrambling to turn the knob to stem the flow of water. After that, he cried. He wasn’t sure how long, just that he had to refresh the water because it had grown cold to finally bathe Sans until he was clean, trying not to linger too long on the scarring. Surely there was some good reason why Sans had remained quiet? Something personal…? Something….anything at all. Anything but him being a horrible brother…

After Sans was dry and dressed; Papyrus didn’t sleep on the floor that night. He joined his older brother in his race car bed, holding his sibling close as his soul glowed faintly to comfort the still monster. Glowing to reassure himself as well. These secrets and discoveries, they had unsettled the tall skeleton. Shaken the very foundations of his world. Sans loved him. These secrets had to stem from that positive emotion, the only thing Papyrus was certain of. That journal Sans had kept had said something ‘killed’ him. ‘Killed them’. Was Sans protecting him from something…?

His big brother felt so fragile right now. The fact that he had 1 HP bounced lazily about the inside of his skull like a taunt.

Papyrus pulled Sans in closer, curling his larger frame around his sibling. Holding him close. The taller skeleton didn’t need protection. If anything…

“It’s my turn, brother,” he murmured against the other’s skull, “I’ll keep you safe from now on.”


	9. Chapter 9

**Summary for the Chapter:**

> We're still on schedule for completion despite me getting sick! So...yeah! (^_^)b
> 
> mercy-run.tumblr.com

_Papyrus walked down the stairs with an extra bounce in his step. Vaguely, he wondered why it appeared like he was crouching but dismissed it as he ran out the front door and into the snow. What was he doing again…? Oh! He was…looking for Sans! Of course he would be looking for his older brother! The skeleton glanced down the street and paused, a frown pulling his teeth down. Was… Was that Sans? Why was he in a lab coat? He had never seen his brother wearing anything akin to that. Had he? Sans was leaning against Grillby’s, his skull bowed slightly._

_He wanted to run to his older sibling. But it looked like… Was Sans crying?_

_The sight of cyan magic streaming down his brother’s face had Papyrus locked in place. The monster couldn’t recall a time where he had ever seen Sans upset, much less crying. It brought an uncomfortable tightness to his soul at the sight. Papyrus was about to call out to his brother when the scenery suddenly shifted._

_What…?_

_He glanced down at his hand, finding a measuring tape in it as he approached his older sibling._

_It was only then that he realized he was smaller than Sans. Confusion ate at the edge of his consciousness as he pleaded with his older brother to measure his height. The smile that stretched across Sans’ skull was both familiar and warm; easing the unsettling sensation of something being amiss._

_"Wowie, Sans! Four feet, four inches. You have beaten me!"_

_His brother offered him a patient look._

_"this isn't a competition, bro. we can do this every year, mark your growth. it will be a good memory."_

_A memory…_

  


* * *

  


Eye sockets fluttering open, Papyrus blinked in confusion at how heavy he felt. How hazy his mind was. He was warm and tucked into his race car bed. Had the skeleton actually fallen asleep? The last thing he remembered was Sans measuring them both at the front-

His soul jumped.

Sans!

Jerking his gaze down, he registered that his smaller brother was flush to his body, small spine to sternum. His arms were holding Sans close and one of his hands had… Papyrus’ entire body grew rigid upon spotting the blue glow shining through Sans’ ribcage. His hand had trailed underneath Sans’ shirt sometime during the night and was gingerly wrapped around the pulsing soft glow of the culmina-

Carefully but quickly, like he had been burnt; Papyrus let go of his sibling’s soul. The blue glow faded but his face was blazing a hot orange at what he had done. It didn’t matter if it had been accidental! Touching another monster’s soul was the most intimate thing you could ever possibly do! And to do it without the other monster knowing…! It was so scandalous, never mind giving his sibling a bath whilst unconscious! Even though he wanted nothing more than Sans to be awake, Papyrus anxiously checked over the smaller skeleton’s expression. Anything at all to indicate he was waking up.

…Nothing…

Papyrus wasn’t sure how to feel. On one hand, he hadn’t been caught fondling his older brother’s soul. But on the other… Sans was still unresponsive. Calming himself and still able to feel the pleasant texture of Sans’ soul against his fingertips; Papyrus took a good five minutes to regain his scattered senses. He had been dreaming… It was strange. The monster had never dreamed about his childhood before. But now that he was focused on it, Papyrus was fairly certain he didn’t remember much about growing up. Had they always been in Snowdin? That had looked like this town. Grillby’s had even been there. But why had Sans been wearing a lab coat back then? Certainly he would have remembered that at least, especially since he had discovered his brother wearing it in the secret room downstairs?

Hadn’t he been absolutely certain Sans had never worn something like that before? But yet… In his dream, it had been clear that his brother had been wearing a lab coat. He had also been crying… Something Papyrus was even more certain he had never seen before…

His skull was pounding something painful.

It was just a dream, correct? Sure, memories were something that grew vague over time, but Papyrus had no recollection of ever remembering something like this. While he was touching Sans’ soul too…

Determined to get to the bottom of the issue, the taller skeleton gently repositioned his sibling and slipped out of the race car bed. Was it a simple dream? His mind playing tricks on his slumbering self because of all that had been happening recently? The tall skeleton walked down the stairs and approached the front door; inspecting the wooden frame. At first glance, Papyrus didn’t see any writing but there was some discolored patches instead. Squinting his eye sockets, the monster scraped a bare phalange against the darker wood; only for it to flake off easily.

Paint…? Some sort of varnish? The details didn’t matter. Papyrus frantically scrapped the substance off only to find…

Numbers…marking height. A bit higher than eye-level. Recent. Painfully recent. And… It didn’t make sense. Papyrus’ memory wasn’t THAT bad! His attention lowered to the next spot and he scrapped it away. Again… And again… Until the lowest and earliest mark. He stepped back, a static roaring in the back of his skull. Three feet and six inches with his name written next to it, with a date. Just above that was four feet and four inches. Exactly like his dream. Exactly…

His skull pounded.

Papyrus had been a babybones, only six-seven at most. All of his except the last had a date. His current height. Sans had stopped growing at four feet and eight inches and none of his had dates alongside them.

…They had been doing this for years. The proof was right before him but the skeleton monster couldn’t believe it! Which was a feat because Papyrus believed in a lot of things! He had absolutely no recollection of this. Why? Why couldn’t he remember this?! It was an important memory. A PRECIOUS memory!

…What else had he forgotten?

His soul sank, remembering the odd notes in the secret basement. They had timestamps for things that had never happened. Could never happen. Papyrus was alive and well, yet Sans had jotted down these things meticulously. Obsessively. Things that Sans knew but Papyrus didn’t. The logic of it was lost on him. But there was the irrefutable fact that this had been haunting his older sibling and he thought it had been important enough to fixate on. Enough to harm himself? Was the machine supposed to do something in relation to this?

If Papyrus couldn’t remember but it had clearly happened; did Undyne or anyone else he knew remember? Those memories had only been obtained through virtue of touching Sans’ soul directly. His flushed faintly but determined to gather more information, the taller skeleton checked on Sans before promising he would be back later.

  


* * *

  


Long after the artificial night had fallen, Papyrus finally opened the door; expression somber and confused. The skeleton had went to every monster asking questions that should be easy to answer. ‘Have my brother and I always lived here?’ Everyone said they had just “shown up” one day. ‘Did my brother work in the labs with you?’ Alphys had gotten a blank expression before saying she didn’t recall Sans ever being a co-worker. She had expressed being confused at the lab coat Sans had been wearing and the lab Papyrus had found. Unsure if he should show Alphys the notes, he had moved onto Undyne. Certainly his best friend would remembering SOMETHING?

“Sans? Heh, it’s funny; when I try to think about it; it’s all blurry. I don’t think your older bro and I were buds. Only thing I remember is him calling after you often.” The Captain had laughed before growing quiet at his distraught expression, “hey, Papyrus. I am sure it’s just my shoddy memory. Plus, Sans was only ever spent time with you.”

That last fact had rung horribly in his skull.

Papyrus hadn’t realized his older brother didn’t have anyone other than Papyrus to be friends with. Sure, there was Grillby; but part of a bartender’s job was listening to customers. From what he gleaned, the people who frequented the place only saw his brother there and did like him but weren’t close.

The skeleton climbed the stairs and found Sans laying in his bed, exactly as he left him. His entire world was shaken as he joined his smaller sibling, holding the only person close that he trusted, thought he knew… Absently, for comfort, Papyrus ‘checked’ Sans.

**Sans**

**LV: 1**  
**HP: 1**  
**AT: 1**  
**DF: 1**

***He loves you.**

Orange magic welled into his tired sockets and he held his fragile brother close, shoulders shuddering in an attempt to keep back the tears. He wanted Sans to wake up and smile at him like he always did. Tell him lame puns. Tell him that everything was okay despite all of these secrets. That he hadn’t been self-centered and not noticed ANYTHING WRONG WITH HIS BROTHER!

For the first time in his flawed memory, Papyrus felt ashamed. He fell asleep cradling his sibling close, tears running down his skull.


	10. Chapter 10

**Summary for the Chapter:**

> We're ten chapters in of sixteen! Chapter sixteen is more of a short epilogue so we just have five chapters left before this is complete. <3 I am still ill but we are so close and I am nearing my deadline.
> 
> If you want to follow me more closely, I have a NSFW blog: mercy-run.tumblr.com

Papyrus woke up as usual without any strange dreams. Sans was still motionless in his embrace, feeling more tiny than the taller skeleton had ever noticed before. He took stock of his brother with worried sockets. It had been nearly a week since he had found his older brother unconscious. That was too long for comfort. It was so similar to… The monster’s slender phalanges absently stroked down Sans’ spine, attempting to reassure himself that his sibling was still whole. There wasn’t a speck of dust to be found; to Papyrus’ relief. Still, he hadn’t dreamed anything new. Which proved his thoughts on that incident being tied to touching his brother’s soul.

He compulsively ‘checked’ Sans; finding his stats to be the same.

It wasn’t as comforting anymore.

Papyrus needed Sans to wake. It was time for another check-up with Doctor Alphys, it seemed. He had bathed his brother a few times, but getting the smaller skeleton to eat was impossible. He needed advice and direction. Hopefully the Royal Scientist could give him that. He got up and dressed in a deep purple turtle-neck, adding his scarf with some regular navy slacks. It didn’t feel right wearing his battle-body. Not with so many changes and uncertainties. 

“Come on, brother. I am taking you in for a check-up.” He murmured softly to his sibling; cradling Sans close to his rib-cage. Papyrus liked to think that Sans could hear him. The house was too quiet these days. Leaving their shared home behind, Papyrus made his way to the Riverperson, ignoring the looks of pity aimed at him. They didn’t know what had happened. Sans wasn’t Falling. The younger brother wouldn’t let him. Couldn’t let him.

He loved Sans too much to ever lose him.

Even though his brother had kept secrets and kept the wool over his sockets. That had to have been born from Sans’ love, a need to protect. It was the only thing that made sense. It was the only thing that was familiar in this horrible situation. The Riverperson watched them board from the darkness under their hood and instead of saying something cryptic, they merely sang as they drifted to Hotland. The song sounded sad, yet hopeful and his arms tightened just slightly on his fragile brother. He still believed Sans would come back to him. Perhaps he just needed help. Going to Alphys was all he could think of, so the younger sibling was more than happy to step out of the boat into the sweltering air near the lab.

Rapping on the metal door; he waited patiently until it opened up to reveal the Royal Scientist. She blinked up at him from behind her spectacles; surprised to see him so early.

“G-Good morning, Papyrus! H-Here for a s-scan?” Alphys smiled timidly up at him, as that was really all she could do. Sans had not been Falling Down the last time Papyrus came here with his brother. He also wasn’t sick, according to any known monster illness. The pressure to fix Sans was there, especially with how sad Papyrus was these days. It was effecting Undyne more than the tall skeleton knew.

“Yes. I would appreciate it.”

He had also toned it down…not like his energetic self. But the yellow lizard couldn’t fault him.

“C-Come in!” She invited and Papyrus entered, approaching the side of her lab she had tidied up for this occasion. It was just a cot and scanner, but it was better than putting poor Sans on the floor. She watched as the younger brother lowered the small skeleton on the cot and hurried to boot up the portable soul scanner. Her eyes darted up to his face.

“A-Any change?” Alphys questioned and the skeleton blinked, looking up from Sans’ face to give her his attention. It really was sad. Not only were they brothers and dear to one another, but they were also Alphys’ favorite secret ship. The second-hand grief from the younger sibling was palpable.

Shockingly, Papyrus blushed a soft orange.

“N-No. He hasn’t moved an inch.”

Sensing she shouldn’t push by his tone, but intrigued nonetheless; she allowed the scanner to work before it pulled up Sans’ readings. Alphys frowned and peered down at them, adjusting her glasses.

“What…what is it?” 

Her attention jerked back up to Papyrus’ face at the waver in his voice before she rushed to reassure the skeleton.

“O-Oh! I-It’s nothing m-major! It’s just…” The Royal Scientist frowned down at a particular string of data, “his m-magical reserves are d-dropping. Probably because h-he hasn’t been able to eat anything.”

A panicked expression crossed Papyrus’ face as he looked down at his brother, “I-I’ve tried to get him to eat! It isn’t the same with other monsters!” Alphys had to place a placating hand on his shoulder to stop him from going into what probably would have ended in a panic attack. She was too familiar with those…

“I know! Monsters similar to skeletons exist, at least in s-some way. You can help his levels rise but,” her scales flushed a deep scarlet, “it’s…kind of intimate.”

The other monster’s sockets blinked down at her for a long moment before Papyrus’ teeth clenched into a determined line, “what do I need to do?”

Her blush deepened and she only kept from squealing because Sans was SICK and it was INAPPROPRIATE at this moment! Bad Alphys! Don’t think about it other than what it is intended to do!

“Y-you are gonna n-need to stimulate h-his s—s-oul!” She squeaked out finally, “he needs m-magic. H-he can’t eat unless d-directed!”

Don’t think about it, don’t think about it, don’tthinkaboutit~!!!

Oddly, Papyrus didn’t appear as embarrassed as Alphys had thought the skeleton would be upon hearing this. His gaze roved over his still brother before he nodded and gingerly gathered Sans into his arms, “thank you, doctor. I will keep you updated.”

She saw them out and when the door ‘whooshed’ shut, the reptilian woman collapsed against it. Damn her sinful thoughts, but that was some creative inspiration for her fanfiction.

——————————————————————

The Riverperson was mercifully silent on the way back to Snowdin and despite the stares, Papyrus didn’t hurry back to their home. Yet, he also didn’t dally. Logically, this was the best and only way to keep his brother stable. The younger skeleton had already trampled on his brother’s privacy unintentionally. If there was a need for it and it meant life or death, he would gladly do it. It didn’t stop Papyrus from being embarrassed though. Touching Sans’ soul had been a pure accident. Actually going through with it to manipulate his sibling to eat though…

That was something a parent did for their babybones. Or maybe lovers?

That thought made him flush a deeper orange and he sighed, shutting the front door behind them. Looking around the kitchen, Papyrus figured that trying to feed Sans his spaghetti was out of the question. The younger skeleton had only seen Sans drink ketchup. It would help if it was a favorite, right? But it was very messy… He sighed and peeked down at Sans’ face, always hoping to find those eye sockets open.

The stillness and slack expression on his brother caused his soul to skip. If Papyrus didn’t successfully feed Sans something, then he really would-

Papyrus plucked a bottle of ketchup from the fridge, his resolve to take care of his brother strengthening tenfold. He wasn’t a babybones. This was unprecedented but he wouldn’t allow Sans to Fall just because of propriety. The tall monster had planned on giving Sans another bath anyways. This would lessen the mess that would obviously come from feeding someone unconscious and he was already embarrassing himself. Why not go all the way? Undyne would surely approve of his mindset.

Marching into the bathroom like he was on a mission, the younger brother put the bottle down and held Sans as he got the water running. Watching the tub fill intently, Papyrus finally spoke to his brother.

“I’m sorry that I am trespassing on something so…personal, brother. Again.” He murmured quietly; his voice bouncing off of the tiles and barely heard over the rush of water, “but… It is very hard not to do. You have a lot of secrets and no matter how great I am, I can’t stop wondering…how much is made up. How much did you lie to me?”

Sans was silent.

The tub was filling very slowly…

“But I believe in you. I have decided not to be angry. There had to be a good reason for you to lie and keep secrets. You are my dear brother. You have always been there for me. I hope that you won’t be mad at me for touching…touching your soul.” His cheekbones warmed with magic.

His brother didn’t say a word.

Shutting off the water and testing it, Papyrus found it to be at an acceptable temperature. He only hesitated a little before sliding the clothing from his older brother’s tinier frame; flinching at the sight of all the pocket-marks in the bone. Especially his sibling’s left hip… Oh… Papyrus blinked, realizing he couldn’t hold Sans up, stimulate his soul and attempt to feed him at the same time like this. He paused a moment more before stepping into the water with his clothes on; before sitting with Sans in his lap. The water spilled over the edge a bit, but he didn’t pay it any mind; focused on his older brother.

Without clothes and all of the damage, Sans looked so fragile.

Papyrus desperately wanted to protect him. It should have been that way for a while. But Sans had continued to protect him. Even with all of this…

“I miss you.”

The skeleton was shocked when his voice came out small and choked. When had he started to cry? Heaving in a breath, Papyrus gingerly summoned his magic and called out to Sans’ soul. The cyan organ flared to life within his older brother’s rib cage and with the utmost care; he cupped the culmination of his brother close. The silky texture of the soul felt so pleasant against his bones. He caressed it and pressed a skeleton kiss to his sibling’s skull.

“Sans…” He slowly regained his composure and reached for the ketchup with his free hand, “let’s get you fed…”

The soul pulsed slightly against his stroking fingers, nearly startling Papyrus enough to drop the bottle. Oh..! He hadn’t expected… The skeleton blushed at the slight glow between Sans’ teeth. Intent must really carry strong with contact to the soul. He hadn’t even been focusing yet it had gotten across what he needed. Hooking the tip of a phalange into the gap between Sans’ usually forever clenched teeth, Papyrus gently pried them open.

“Wowie…”

Papyrus hadn’t expected the four sharp canines that fused seamlessly with the set of his sibling’s mouth. He had never seen Sans’ mouth all of the way open! At least…he didn’t think so??? His memory didn’t seem to be the most reliable. His fingertips playing along the edge of his brother’s soul, the skeleton turned his attention to the glowing appendage within. Was it possible to die of embarrassment? Still… He peered intently at the sight, mesmerized. Sans’ magic was a pretty blue. Papyrus’ favorite shade of blue. Perhaps even his most favorite color. The larger skeleton found himself comparing their mouths. He had two sharp canines, with two prominent incisors on his jaw. His tongue was more slender than Sans’ and longer. Sans’ tongue was very nice though. Rounded and smooth.

His soul squirmed and grew warm.

What…what was he doing? He was supposed to be feeding Sans! Not…not staring at his fangs and conjured magic like this. Focusing, Papyrus squeezed the liquid onto Sans’ tongue. A copious amount, maybe. It really looked good sliding down into his brother’s conjured throahhhat was he thinking??!

Papyrus would disappear if he could, his blush burning.

He wasn’t stupid. Maybe naive, just a little. But… He froze. He was looking at his brother in a non-familial way. His chest glowed as he awkwardly came to grips with that. His sockets tore away from his brother’s mouth to the soul in his hand. Was it because he was holding Sans’ soul? Maybe he liked his partners small? Papyrus had never even thought of romance or his preferences other than owning a book on dating. In the case that someone did show interest, he liked to be prepared for anything.

The skeleton hadn’t been prepared for this.

Papyrus… He… He was attracted to his brother.


	11. Chapter 11

**Summary for the Chapter:**

> I hope you enjoy this update! We are still on schedule for completion by the end of the month despite illness and such. <3
> 
> Mercy-Run.tumblr.com

After dressing Sans carefully and tucking him into his bed, Papyrus took a step back and simply staring listlessly at the other skeleton. The glow of the other’s soul was still present underneath the fabric of his shirt. He could still feel it’s soft texture against the tips of his phalanges. Still picture the process they had went through with his soul fluttering against his rib-cage.

Papyrus had always loved his brother. He hadn’t really been interested in dating or romance, though the idea of it was appealing. The skeleton had just wanted to be surrounded by a lot of friends who thought he was talented and cool. This had…come as a surprise… Even with his faulty memory, the younger brother felt a certainty that was absent everywhere else in his mind. That this was the first time he had thought of Sans in this manner.

They were related, yes. And there had been a ban on bonding within the family when monsters had first been imprisoned in the Underground due to low population and wanting to build their numbers once more. Papyrus was familiar with their history. Though the skeleton never expected to focus on that aspect in particular.

He certainly was now.

That thrill of arousal was purely sexual. The taller monster would have passed it off as a fluke if he hadn’t gotten so very fixated. That thrill had pierced him deeply and left him with a feeling. A notion. That Papyrus would never be able to go back from now that he had discovered it. It was like a hazy film over his world-view had been lifted and the culmination his being had resonated with his brother’s.

Papyrus loved Sans. In all manner of that word. Completely and utterly.

It just felt right. Like the satisfying click of the last piece of the puzzle sliding into place just as it was meant to be. He had never been one to deny his feelings or instincts. But… What did he do with this information? Papyrus couldn’t tell Sans. He didn’t really even KNOW much about his sibling. …Just that it felt perfect. Had he been blind before? Or just not…remembered? It seemed like his brother knew a great many things he did not.

Papyrus absently ‘checked’ the small skeleton with a gentle expression.

**Sans**

**LV: 1**  
**HP: 1**  
**AT: 1**  
**DF: 1**

***He loves you.**

Frustrated tears welled up in his sockets. Instead of comfort, those words caused an unpleasant pang of pain and loss in his chest. He couldn’t let Sans Fall Down, now more than ever! Just the other night, touching his sibling’s soul whilst sleeping had triggered memories. He was certain those dreams were memories.

Touching another’s soul was a great act, reserved for lovers and bond-mates. It was taboo to do so without the express consent of the monster. Everyone knew that. It was ingrained in their make-up. Even thinking about it had him reeling but… Papyrus had to do it. He just knew too little and this was how he could learn. The monster would find a way to save his brother somehow. The answer had to be inside those strange disconnected memories.

“I am sorry, Sans.” Papyrus murmured softly as he slid into bed with his smaller sibling, “but I love you. I love you _so much more_ than I had even realized. I cannot lose you now. I hope you can forgive me.”

With a gentle hand, the younger brother slid his grip up Sans’ white tank top and grasped the faintly glowing inverted heart. It felt so very soft and so very warm. It felt safe and wonderful and like home. Stroking the organ softly, Papyrus allowed his own to shine, pulsing in tandem with his brother’s until the sensations pulled him under.

 

* * *

 

  
There was a baby crying somewhere, the skeleton registered faintly with alarm. Everything was dark and dull. He couldn’t make out his surroundings at all but Papyrus felt so very weak and lonely. He was laying on his back and couldn’t find the will to move. The crying ebbed into soft whimpers. Why was he alone? Why was no one with him now? The skeleton had been sure there was supposed to be people with him.

Another faint whine and Papyrus realized it was him making that heart-breaking noise…

Why was it dark? Where was anyone? The monster felt so sick and so very light.

And then suddenly, he had to squint his sockets as a shadowed figured rushed over to him. They must be so very big to be able to pick him up like that. As big as the King. Please… He needed help…

"brother..."

  
What? Brother…? His sockets slid open and peered up into a face that was both familiar and so very strange at the same time. His soul ached. It was Sans! It was his dear brother! Oh! But Sans looked so…so young! Just a babybones! What was going on? This couldn’t be right! His brother was a lot older than him!

  
Even though he wanted to speak, distressed huffs for air was all Papyrus could manage. Was he dying? None of this made sense! Were these just dreams and not memories? Had he been mistaken?? The warmth from his older brother’s young body seeped into his cold bones as the other monster held him close like a treasure.

  
Beautiful and breathtaking azure light filled the gloomy room, casting it’s splendor on the dismal surroundings. A room. Papyrus’ room to this day. But it seemed bigger, filled with baby toys and filth.

  
It was suddenly easier to breathe. The cold went away and the skeleton was finally able to see what Sans was doing. There was a stream of magic flowing from his older brother’s soul and into his; surrounding it. Small and dim, barely glowing.

  
Sans’ **HP** …

It was falling!

  
That was wrong! This wasn’t right!

  
**19/20...18/20...17/20**

  
Sans was hurting himself! Why was he hurting himself?? The expression on his sibling’s face was pinched with agony, the other monster’s teeth parting to bare small fangs in a quivering display of self-destruction. This wasn’t how healing worked! What was…?!

  
**16/19...**

  
No! No! Everything about this was screaming to his instincts to make Sans stop. His brother should never ever harm himself for his sake! But then the small skeleton was holding him close, like a lifeline. Forcing through the pain without a second thought about himself. Papyrus felt like he could cry. That he could scream at Sans in true anger. Why?!

  
It felt like forever until his sibling pulled back. There were dim digits wafting away from the act the other monster had committed.

  
**1/1 HP.**

  
It felt like a death blow. A horrible truth. This WAS a memory. It was a memory. And it was his fault that Sans’ Hope was so very low. The other skeleton was humming a soft mindless tune, rocking them both before meeting his searching gaze.

  
And Sans’ expression shifted into the most radiant smile Papyrus had ever seen. His entire being quivered from the warmth and love and OPEN expression his sibling was giving him.

  
"h-hey there, papyrus..." The tiny version of his brother greeted in a rough whisper and Papyrus felt himself smiling back. It was probably how this really went with the monster having no real input. This had already happened, there was nothing he could do to change the past but…

  
Sans’ eye-lights were dancing with happiness despite what he had just done, chuckling and touching their foreheads together affectionately.

  
"i'm your big brother. i'm sans."

  
Oh Sans… With his adult mind, he fully understood the gravity of what happened. He had been left alone. They had been left alone. Unwanted. Abandoned.

  
"i don't know much about babies," the younger version of Sans murmured, drawing water into a sink. It was their house but it looked awful.

  
"but i will take care of you. i promise."

  
His soul cried out that his brother had already done enough. Was this the first time they had met? The other skeleton was so very tiny and young!

  
"i will protect you, lil' bro. no one will hurt you from now on. i swear."

  
…He had been right. Despite all of the secrets and lies. Everything had been for his sake, to protect him. Papyrus felt unworthy, overjoyed, ashamed and so very blessed. Oh brother… His soul cried out for this open and loving young vision of his sibling. He wanted to plead with the memory Sans to wake up. Please… But this was the past. His cries were an echo of a memory inside a dream. His soul pulsed and reached out into the encroaching darkness.

  
And no answer came.


	12. Chapter 12

**Summary for the Chapter:**

> *I'm afraid... 
> 
> Feeling a little better! Going to try for a double update today! Have some angst!
> 
> NSFW blog: mercy-run.tumblr.com

Papyrus found that exploring Sans soul was a delicate process. He could never uncover what he intended on finding out and viewing everything at one time seemed too dangerous for his brother. The skeleton was ashamed to admit it had become somewhat of an addiction. Caring for his unconscious sibling was oddly fulfilling, especially as he viewed more memories that revealed just how much his older brother had given up. Papyrus would feed, bathe and talk to Sans throughout the day, fighting against the compulsion to touch his brother more inappropriately as his feelings grew with each lost fragment returning to him.

Falling asleep with Sans’ soft, glowing soul cradled in his hand was so pleasant.

But on the opposite spectrum, Papyrus also found himself going through many mood swings that were uncharacteristic of him. Though, the skeleton supposes that this wasn’t a normal situation. Still, his shame at how much he had forgotten, his frustration against not helping his brother, the anger aimed at himself for not realizing that Sans had given up absolutely everything for his sake and Papyrus hadn’t been the wiser. Each night had him remembering more and a raging protective instinct had him not leaving his sibling alone for a minute.

Each night, he was both looking forward to and dreading falling asleep with Sans in his embrace. Sometimes the memories were precious things Papyrus hadn’t believed he had forgotten. His brother sacrificing his HP had just been the tip of the sacrifice his older brother had made. He had found out Sans was just a mere four years older than him. Sans hadn’t gotten the luxury of being a babybones. His brother had invited Undyne into their home even though he hadn’t needed to. They had been friends for much, much longer than the monster had remembered.

There were just so many things he hadn’t recalled that he was unlocking in the deepest reaches of Sans’ soul.

Sans taking him to his first day of school with other monsters. How terrified he had been of letting go of the only monster he absolutely trusted to being surrounded by monster children he was afraid would hate him. Sans putting up with him as a baby without a single complaint or raised voice. Sans smiling beautifully, nearly in tears when Papyrus first said his name. Being reassured over and over that he would get friends, that there wasn’t anything wrong with him. How he himself had gotten that blue coat Sans refused to take off these days for Giftmas after noticing Santa never brought his brother anything. Finally growing taller than his brother and boasting about it, much to his shame.

His brother’s stunted HP was likely the cause for why he was so small. So frail.

But as he kept delving through these memories, Papyrus was wondering if maybe that wasn’t the only cause. His older brother was constantly tired and with his older and keener mind being present in these lost moments, he began noticing a lot of things he had missed before.

How Sans didn’t smile at all anymore like he used to; able to muster anything halfway genuine for only Papyrus. How it had been a fluke that he had seen Sans in that lab coat at all, it seemed Sans didn’t wear it in his recovered memories at all besides that one time. How he didn’t cook anymore or keep up his appearance. How he really didn’t EAT anymore. How the entire world seemed to be weighing on his tiny frame despite his puns and fixed smile.

…How unhappy Sans actually was but managed for his sake.

Always, forever for Papyrus’ sake…

Sans always seemed to be an echo in these memories, present but not able to be reached no matter how much Papyrus’ soul called out for his dear brother. But thankfully, it seemed his brother was stable despite being unconscious. A month of searching through his sibling’s soul had yielded everything but the skeleton had a creeping suspicion that there was something big coming. Something unpleasant that shadowed every single one of these memories. A missing piece of the puzzle. A crucial piece that he needed to understand.

So before settling next to his brother’s small body that night, Papyrus focused on what he wanted as hard as he could. Changed his question from ‘how do I wake Sans up’ to ‘what do I need to know? What is missing?’

And that night, after a month of searching Sans’ soul for answers; as Papyrus’ consciousness slowly faded as their souls glowed in tandem…was the first time Papyrus experienced a pang of terror right before easing into sleep.

 

* * *

 

_This was different. He shouldn’t be here. There was an all-encompassing feeling of wrongness smothering him. Papyrus came to, the surroundings unfamiliar in a wrenching way. It was an office, sterile and too bright. There was a desk that was meticulously tidy and in order. The skeleton may have taken a moment to appreciate it if his entire being wasn’t screaming unease, disquiet, and foreboding._

_He had never been here. Papyrus was one hundred percent certain!_

_Especially with all of his lost memories returned to him._

_But if this wasn’t his memory then…?_

_His musings were interrupted as his body tensed at approaching footsteps. His body reacting on it’s own wasn’t anything new. All of these memories had a set script. It had already happened. No input from his mind, no matter how much he may want to budge a single phalange mattered. However he wasn’t used to the emotions that crashed through his being. Papyrus would have cried out in alarm at how strong and sharp they were._

_The amount of despair, panic and dread was breathtaking. All-consuming. Papyrus had never ever EVER been anywhere close to being this afraid in his entire life. The monster hadn’t known that it was possible to feel terror of this magnitude. But he was feeling it. Oh stars, how he was feeling it…_

_A monster stepped through the door. A skeleton. Papyrus was floored underneath the increasing waves of anxiety, his breathing quickening to a light panicked pace. He was tall, his bones a pristine white. As clean as his white lab coat. His eye-lights were bored, expression pulled into professional disinterest. His hands had elegant phalanges, similar to Papyrus’ own; but there were holes gored out of his palms. This monster looked every bit the model scientist. A formidable and intelligent skeleton._

_Humans oftentimes threw their religious books away and they would appear in the dump. The faded ink would speak of a fantastical evil that was the source of all wrong doing and ill-intent within it’s pages._

_His entire being was rejecting and terrified of the sight of this monster. It had Papyrus convinced this was who those books were referring to when referencing their ‘devil.’_

_The skeleton barely offered a glance in his direction as he walked over to a cabinet and began taking out too many syringes to count. Their glass chambers were filled with glowing liquid that caused Papyrus’ non-existent stomach to squirm._

_There was just so much fear! Papyrus felt like his soul would burst from it and he would dissolve into dust. He couldn’t find his breath, his thoughts were scattering. How could he had possibly forgotten something like this?!_

_“I have little time for you today, so I will make this quick.” The skeleton’s voice was refined and smooth. But the dialect was strange. Something Papyrus only knew by instinct but was certain he had never heard before._

_His body jerked as the man drew closer, flinching but unable to move. Papyrus was restrained, he realized in horror. He couldn’t get away from this horrible monster. The other was so very wrong. So, so wrong and horrible!_

_He barely registered himself keening low in his rib-cage, the sound broken and fearful as a syringe was primed and the skeleton encroached into his personal space. But he couldn’t seem to help himself in watching what was going on. No, it had been what had happened. He had watched. It was too horrible to look away from! Especially if he decided to do more..._

_Papyrus lowered his gaze, following the needle’s progression as it neared his left hip. His bare left hip that… That…_

_The younger brother’s soul stuttered._

_Oh stars! Oh no! This couldn’t be! He recognized the mutilation found there. The skeleton saw it everyday now._

_This was Sans! Had he really regained all memories and had moved onto ones where he wasn’t present?!?!_

_He had no time to think as the thick needle plunged into the already devastated bone, pain unlike anything Papyrus had felt before engulfing him. Sans screamed and his own horror piled on top of what was already staggering. The younger brother had never heard his sibling raise his voice. Had only seen him cry in memory. The sound called to everything that made him who he was to protect Sans, to stop this from happening._

_No! Why was this happening?! It hurt so, so badly!_

_Another needle, more pain, more screams from his fragile brother that he wished he could wipe from his memory. And then words…_

_“p-please! i can’t, please, i can’t, please stop, i can’t!” Sans was begging brokenly._

_“You know what is at stake if you refuse me, Sans.” The doctor said in a dangerous tone._

_Papyrus wanted to shield his precious sibling. Please, don’t hurt my brother!_

_“please don’t hurt my brother!”_

_W-What…? The skeleton thought for a wild moment that he had somehow changed something in this memory when Sans’ words continued, “anything but papyrus!”_

_No… No. No.No.No. NO! The younger brother’s soul pounded painfully. This was too much! Sans had already given too much for his sake. Far too much!_

_The doctor leveled them with an unimpressed but mildly interested expression, “I wonder how your mind works sometimes. You are brilliant, I know you have the capacity for it. Why do something this idiotic? You know I am blackmailing you. You know I don’t have clearance for this. Why do you allow this to continue?”_

_The scientist appeared genuinely intrigued as Sans tried to find his words before speaking past his tears into the suddenly too quiet office._

_“papyrus is happy. nothing else but that matters.”_

_The answer was clearly a disappointment to the monster, “I would have thought any monster I sired would have been much wiser.”_

_This skeleton was their father… This cruel man was their father… The screaming, pain and experiments continued._

 

* * *

 

The next day, Papyrus couldn’t bring himself to leave the bed; sobbing and choking on orange tears as he refused to let go of Sans.


	13. Chapter 13

**Summary for the Chapter:**

> *...i'm so alone...
> 
> And the second update for today! <3 Thank you for reading and supporting me!
> 
> NSFW Blog: Mercy-Run.tumblr.com

The tall skeleton couldn’t bring himself to delve back into Sans’ memories after that horrible night for more than a week. Papyrus spent four days of those simply grieving for Sans and what he had been through. It also had hurt experiencing a trauma second-hand like that. Like it had been happening to him instead of his sibling. He also was more clingy if that was possible and when he had to finally leave the house at the insistent inquiries from Undyne; the monster took Sans with him. His state had worried his best friend and he had confessed to what had been happening.

He was deeply ashamed at touching Sans’ soul without permission, made that much worse by Undyne’s look of shock when Papyrus told her that had been what he was doing. But the mystery of why there were so many holes in Papyrus’ memory had immediately distracted her from the taboo. And oddly, whenever the skeleton would bring up a memory they had shared, Undyne had expressed delight and then shock at having not remembered it either.

So it wasn’t an isolated event, backed up with how Papyrus told her the town’s people had forgotten everything as well. It had unsettled Undyne deeply and when Papyrus asked after another skeleton being a scientist, her expression became blank for a moment before she exploded with frustration.

“It feels like it’s at the tip of my tongue but I can’t remember! Ngah!!” She had tugged on a fin to ground herself before becoming resolute, “if it is science-related, we will need Alph.”

So Alphys had gotten involved and currently, they were both in the main lab after Papyrus had given the Royal Scientist Sans’ notes. It had felt like a violation, but wasn’t everything he had been doing thus far been a lot worse?

But seeing everyone work so hard to figure this out while he wasn’t doing anything out of fear…

Papyrus had to continue exploring Sans’ soul. His brother had to be in there somewhere. He hadn’t Fallen Down. He was just sleeping. Surely searching through the culmination of everything that made Sans himself would reveal his sibling deep inside. He needed Sans to wake up, now more than ever. The skeleton couldn’t give up now even though he was afraid to experience something horrible again. Sans had lived through it.

And all for his sake.

His determination and resolve returned with that thought. He laid in bed with Sans, holding onto the smaller skeleton and stroking the other’s spine to sooth them both. Before, Papyrus had meditated on what he had wanted and he had gotten something he ‘needed to know.’ It had seemed to give him direction so maybe he needed to focus on something else. ‘Waking up Sans’ or ‘finding Sans’ hadn’t yielded any results, just his lost childhood memories. He needed to change his approach.

Something secret, definitely. Something he needed to know. A missing piece of the puzzle to make Sans whole again. Something that was important to Sans.

He concentrated on those things and sank into darkness…

 

* * *

 

_The familiar words of Fluffy Bunny being read in his brother’s soft tone eased the tension Papyrus had felt before falling into Sans’ soul. His eyes were closed and everything was dark, but it was safe. This was a good memory. Nothing scary, no terror and pain to tarnish this memory. They were okay._

_“…paps?” He heard his brother question and his soul thudded painfully. Oh how he had missed the sound of Sans’ voice! He didn’t care if his sibling grew angry and yelled at him with that voice as long as he could hear it again in the waking world._

_“…are you sleeping, bro?” Sans questioned again, a tad louder than before but his body didn’t move. He really was asleep because he didn’t stir when a small hand gingerly touched his cheek. His soul swelled with love at the gesture. Papyrus missed Sans so badly!_

_“heh. you must’ve been exhausted…”_

_There was the sound of a book closing and Papyrus felt alarm ring through him. No! No, Sans couldn’t leave! What was the point of this if not to find a way to help his brother?! He wanted something important! Something secret!_

_The footfalls of his brother stopped at the door and he felt despair well up in him. Why was he remembering this if it wasn’t important? Sans was leaving and he was just sleepi-_

_“would you be disgusted with me?”_

_He had barely heard Sans’ words not only because he had been frustrated but also because they were barely a whisper from the door._

_Sans hadn’t left._

_“…i’m disgusted with myself.”_

_What…?_

_Sans’ sighed deeply, “i’m sorry i feel this way. it’s abnormal. it’s not right of me but i can’t seem to stop…”_

_…What was Sans talking about?! There was nothing his brother could do to make him think less of him. Sure, consuming ketchup and leaving socks everywhere was disgusting but Papyrus was pretty sure that wasn’t what brought this on._

_He heard the gentle footfalls of the small skeleton returning to his bedside and that hand was back, gently stroking his face._

_“i’m so dependent, it’s so disgusting.” There was that word again. Papyrus wanted to shake sense into his brother. Nothing about Sans was ‘disgusting’!_

_“you’re all i have, bro. and…i don’t need anyone else. i don’t want anyone else.” There was an undertone there that made warmth coil in the younger skeleton’s soul. That… This almost sounded like…_

_“heh…heh heh… i can’t make myself stop. i’m so sorry.”_

_The bed dipped near his shoulder and Papyrus’ mind quieted completely as a gentle touch brushed against his temple. Then his cheek… The press of teeth, the nuzzle of bone. So soft, so afraid to wake him up, so gentle…_

_“i’m sorry…” The words were soft but thick with emotion. There was the gentlest pressure against his mouth, wet with what had to be tears…_

_Sans was kissing him…_

_Not on the forehead or on the cheek like family members did. His brother was kissing him tenderly on the mouth. Like a lover…_

_“i love you so damn much, papyrus.”_

_Oh..._

 

* * *

 

 

With a sigh, Papyrus woke up. It hadn’t been like last time, where he had awoken screaming. Or like all other times before, where the skeleton had woken up feeling thoughtful about the memories returned to him. No. It was gentle and gradual, followed by warmth.

The soul in his hand was pulsing from the phantom memory, a love so great yet a shame that ran deep.

Sans loved him. Had loved him for a very long time now. Long, long before Papyrus had his own revelation in the most embarrassing of ways. The tears that leaked from his sockets were slow and warm. Happy.

“Oh, Sans…” Papyrus breathed out, stroking a thumb gently over the softness of Sans’ soul. His brother loved him, so so much. So much it was nearly a physical ache. And in this moment, a solution came to the younger skeleton. One that may upset his brother. One that would have him jailed if any other monster found out. But Sans was worth it.

As long as Sans was happy. Was safe. Then Papyrus was happy.

Which was all that mattered to Sans.

Inhaling a deep breath, Papyrus gently untangled their forms and fixed the bedding around Sans; not letting go of the glowing inverted heart that belonged to his brother. Staring down at his unconscious sibling only steeled his resolve. So in a burst of light, his own soul answered his summons and he took it with his free hand. His sockets trailed from his soul to his brother’s.

They looked like they belonged to each other. That thought comforted him. Sanses shouldn’t be without their Papyruses. And Papyruses shouldn’t be without their Sanses. He would wake his sibling up…

The first contact of his soul brushing the softness of the smaller skeleton brought an intense wave of pleasure and emotion. But he persisted, gingerly coaxing with his intent to bond. Sooner than he was prepared, so quickly in fact that he nearly missed the spectacular sight of their souls joining in a beautiful burst of light, they bonded. Quick, simple and permanent.

Startled, he allowed both souls to return, still feeling his brother just as acutely as if his soul was still pressed against his own orange. It was the only reason he looked up when he did.  
His brother’s face shifted minutely before a soft groan followed; Sans’ eye socket’s finally peeking open. Papyrus felt elation wash through him, which confused his brother as he felt it second-hand.

Sans was awake.


	14. Chapter 14

**Summary for the Chapter:**

> *i never want to let you go...
> 
> I plan on completing this today! <3 Prepare for smut in the next chapter. ^_~ It is long overdue!
> 
> NSFW Blog: mercy-run.tumblr.com

Papyrus’ soul felt like it was beating against his rib cage like a frantic bird as his older brother stirred, confusion pulling his teeth down; those white eye-lights flickering into existence in Sans’ sockets. The smaller skeleton blinked and turned his head, noticing him.

“bro…?” 

Unable to bare it for a moment longer, the tall skeleton lunged forward with a relieved cry; pulling his sibling into his embrace. His brother tensed but didn’t push him away.

“Oh stars! Sans! I am so happy!” Papyrus exclaimed, “I thought you were never going to wake up, brother!”

“w-what? wake up…? what happened?” The second-hand confusion was drifting through their brand new connection. The younger monster wondered if Sans could feel it or just was that disoriented that he wasn’t thinking straight. Unwilling to let go of Sans but needing to explain himself, Papyrus drew back enough so that he could meet his sibling’s confused expression.

“I found you unconscious in the basement.”

Sans’ eye-lights shrank to mere pinpricks at his words. Oh no, if that was enough to put his brother on edge, he was certain the rest of the news would not go over well at all. Papyrus took a moment to steady himself. He had to be firm. Had to own up to what he had been doing to his brother. About everything he had learned.

“You have been unconscious for over a month.”

“a…month?” It sounded like his brother had merely parroted that back to him in his shock. Papyrus nodded solemnly.

“Yes, brother. I took you to Doctor Alphys fearing that you were Falling Down, but she assured me that your levels were stable. I’ve been taking care of you since then but… I have done you a great injustice, Sans. I do not know if you will be able to forgive me.”

Sans’ confused expression finally faded as he shook his head, concern softening his eye-lights, “papyrus… i’m sure it wasn’t that bad. i could never be angry at you.”

The familiar comforting tone of his older sibling’s voice caused orange magic to well up in his sockets, “no, Sans. You do not understand. You will surely be unable to forgive me for what I have done to you.”

The smaller skeleton remained quiet, radiating confusion and concern. 

“I have been touching your soul without permission.” Blunt, straight to the point. Sans’ breath hitched, his eye-lights nearly swallowed up by the darkness of his eye sockets as those words sunk in. Papyrus was certain his brother might possibly never want to associate with him again. But he owed Sans this much and more.

“papyrus…? w-why would you do that?” The smaller skeleton questioned, a tremor in his voice.

“It was an accident the first time! But I had a dream when I had touched it. No, I- It was not a dream, it was a memory, Sans. I-I know why your Hope is so low!”

Sans was still and silent. If not for his now darkened sockets being open and trained on his face, Papyrus would swear his brother was still asleep and locked away from him. A long moment passed and it became clear that his brother was frozen from the information, so he continued even though it would make Sans even more upset.

“I wanted to wake you up more than anything and I did not know how to do so! You kept so many secrets from me, brother. It was like you were a stranger! I was upset, but I forgive you! I know you only wanted to protect me. I know I had forgotten so many things and exploring your soul each night returned such precious things to me!”

Sans was silent, his attention riveted on what he was saying. It was obvious that his brother was scared and horrified by what he was saying. He could feel it through their brand new bond.

“I remember you sacrificing your Hope for me as a child. I remember saying your name as a baby and your expression. I remember meeting Undyne at Waterfall and you welcoming her into our home. I remember- Sans?”

Blue tears spilled from his smaller brother’s sockets, relief washing through their souls, “oh…oh stars. oh, paps. you- you remember!”

Oh. Oh! His brother had been alone for so very long with this... But he wasn’t finished!

“Sans, please hear me out. I am not done.” His brother nodded shakily, “I remember measuring our heights each year. I remember giving you that blue coat for Giftmas. I remember so many wonderful things…”

He couldn’t share that he remembered their father. That he had been in that memory with Sans as they were both terrified and hurting. That was something Papyrus would keep with him until he turned to Dust. That would only harm Sans, as much as he liked to be truthful. It would only distress his sibling and he had already did so much to Sans without his consent.

“I…I also know, brother. Your feelings about me, Sans.”

The relief in their bond cut off like a switch had been flipped, the horror returning tenfold. Sans grew rigid, the magic that usually welled up before his sibling took one of his ‘shortcuts’ building but Papyrus didn’t let go; knowing if his brother did that while they were touching it would be futile to use as an escape.

“Sans. I love you too. I love you like you love me.” The taller skeleton murmured softly.

His brother began shaking his head, “no, no, paps… you are saying that because you feel like you have to-”

“NO!” Papyrus shouted so firmly and loudly that Sans’ startled in his embrace, “no, Sans! I had realized it before I had seen that memory! Of you reading me Fluffy Bunny and what you said while I was asleep! I found out a month ago, soon after you had that accident! I know how I feel! I’m not a naive babybones, especially not anymore! That is why I committed such a sin to wake you up! I-”

His resolve failed him under the weight of what he had done, “I have done such a horrible thing to you, Sans. I know you love me. As more than a brother. Those feelings are not one sided anymore but… I have done a terrible thing…”

Sans’ eye-lights slowly eased back into existence, searching his downtrodden expression intently.

A long minute of silence passed between them before his brother broke it with a tentative call of his name, “papyrus… what terrible thing?”

“We… I…” Papyrus was at a loss for words in the face of what he had done with little thought. He wasn’t sure he could bear Sans’ hating him over what he had done.

“paps…?” Sans’ voice was pitched soft and soothing again.

“I remembered when I was in touch with your soul,” he began, “I didn’t want you to be alone anymore. To be the only one that remembered. I know that something strange with time has been happening. And I love you so much, Sans.”

His gaze locked with his elder sibling’s, “do you not feel how much I love you, brother?”

And Papyrus focused on everything he had learned. On how much he adored and loved his brother. How precious Sans was. How he could never repay him for everything he had done for his sake. How he felt lust and warmth while caring for his sibling. How embarrassed he had been when doing so. How desperate he had been to wake Sans up that he had done the unspeakable.

It was obvious the moment Sans realized what he had done. The tell-tale glow of their souls through their clothing was a clear visual giveaway. The emotions that weren’t his older brother’s own cementing the fact. There was an overpowering feeling of shame and fear. Sans was ashamed that Papyrus had done for his sake. Fearful that Papyrus had done this without knowing the full consequences. Scared and overwhelmed.

But then, he slowly relaxed as the truth of what his younger brother was saying sank in, reinforced by powerful and pure emotions. A soft blue glow tinged Sans’ skull as Papyrus leaned forward and touched foreheads with his brother. Like that young version of Sans had done with first greeting him as an infant.

“I don’t regret it, brother. I will never leave you. It is my turn to protect you and if you will have me… I want to be by your side forever. I do not ever want to let you go…” His right socket smoked with orange magic as he stared into his precious sibling’s eyes.

“paps…” 

“I love you, Sans.” He whispered.

His brother sobbed, his tone choked as he finally answered with a smile. A genuine smile, so like the one that was first gifted to him all those forgotten years ago.

“oh stars, papyrus, i love you so much!” Their shared souls pulsed with elated and overjoyed energy, basking in the acceptance of their new bond.


	15. Chapter 15

**Summary for the Chapter:**

> *Together at last.
> 
> NSFW Blog: Mercy-run.tumblr.com

After that intense confession, Papyrus and Sans had moved to lay together on the younger skeleton’s bed. Their souls were still glowing happily as they both basked in each other. The tall skeleton felt like he still deserved Sans’ anger, but in retrospect he should have known better. Sans had never once gotten angry with him, why would his sibling start now? Even in the face of such a horrible trespass, his brother was like he always had been. Loving and gentle. Always here for him. Always…

His long phalanges stroked Sans’ cheek and a small tremor went through his older brother, hazy eye-lights trained on his expression. They were happy. They were together. There wasn’t a wall between them, built of secrets and fear.

Papyrus wanted to go that one last step to cross over that invisible line that had kept them apart. To go from brothers to lovers. It reverberated from his soul, that need and Sans’ breath caught, eye-lights searching his.

“papyrus?” He questioned, tone soft.

“I want you, brother.” Papyrus confirmed and the small body in his embrace shuddered before an answering pulse of need rang through their bond.

“please…”

Now that he had permission, Papyrus rolled them over until Sans was below him, his larger body hovering over his older sibling’s. Like this; his brother seemed so small. He was, his mind reminded. Sans was fragile and had been through so, so much. But now it was okay. Now it was his turn. The younger skeleton would protect his precious brother. But for now, he wanted to make them both feel good.

Take that one last step…

Desire curling warmly in his soul, Papyrus closed the distance between them and placed a skeleton kiss on Sans’ mouth, drawing a sigh from his brother. One of the smaller monster’s eye-lights faded, leaving his left pupil to phase into that lovely blue. To his delight, his sibling parted his teeth, revealing fangs and that tongue that Papyrus hadn’t been able to stop thinking about.

His own slender orange appendage darted out to meet Sans’, curling a few times around it and stroked, tasting. Sans was sweet and their magic meeting had both siblings moaning. The slow slide of slick tongues had arousal shooting down the younger skeleton’s spine and when they parted, Sans was panting and blushing.

Papyrus leaned back and tugged off the sweater he had worn to bed, small hands pressing against his revealed rib-cage. He trembled as his older brother greedily touched his floating ribs, stroking them and pulling him back down into another breathless kiss. The younger skeleton could feel his magic pooling in his pelvis already, made intense as their emotions rang through each other due to their soul bond.

He carefully slipped the shirt off of his brother, who looked frightened for a moment as the wounds in his shoulder and spine were revealed. But Papyrus quickly distracted Sans, laving his dripping ecto-tongue over the marks marring his sibling’s bones without a single word.

“oh, stars!” Sans gasped, small spine arching off the mattress into Papyrus attentions. He had feared that may have hurt his brother, but they seemed to be sensitive. It made him wonder… Lowering the other’s black track-shorts, the taller skeleton paused as another bolt of fear ran through their connection before lapping at the ruined bone of Sans’ left hip.

“fuck! oh, please! paps!”

A pleased orange flush heated his bones at Sans’ enthusiastic response, doubling his ministrations against the pitted area. His serpentine tongue left a slick trail of orange magic over the old wound, drawing cries of pleasure from his older brother. It was not even a moment later that Papyrus noticed blue magic attempting to form in Sans’ pelvis and he pulled back to allow it.

Sans’ face was flushed a dark blue as Papyrus surveyed the ecto-organs created for him. All of it was in that same shade of blue as his sibling’s soul, a shorter but girthy shaft already leaking a bead of magic and below that; a puckered entrance. Oh stars…

“You are so very beautiful, Sans.” He praised. If his brother could explode from blushing magic, he was certain the smaller skeleton would be a goner. He bent down to lap the rogue droplet of magic from the tip of his brother’s cock, drawing a whine before he moved even lower. The tip of his ecto-tongue circled the small entrance and Papyrus had to hold Sans steady as the other began to thrash. Being gentle and careful of Sans’ lame hip, he dipped his tongue into the magic, withdrew it and then gently coaxed it to loosen enough.

“papyrus!!” Sans shouted as the magic finally gave and allowed the taller skeleton to snake his tongue deeper. His orange magic made their joining slick quickly and obscene wet noises accompanied his brother’s cries of pleasure. Once his tongue was gliding effortlessly as deep within Sans as he could go, Papyrus withdrew.

His brother was trembling as Papyrus checked one last time.

“May I have you, brother?”

“yes, oh please, paps. yes!” Though his words were frantic, the younger monster could feel certainty and conviction inside Sans’ being. Reassured that he at least got consent for one thing in their changing relationship with each other; he lowered the soft gray slacks just enough to free his own magic. It had formed a long member of his own, definitely not the first time it had happened. He may have been naive, but was definitely not completely innocent.

His brother moaned as he teased the head of his cock around the relaxed entrance before carefully pressing forward. It slid inside and the tightness and sweet noises brought overwhelmed tears to his sockets.

“Oh brother, you feel so wonderful!” He gasped as he sank deeper; Sans’ small legs wrapping around his pelvis as his arms flung around Papyrus’ neck. He was nearly bent in half to hilt completely into his smaller sibling. He peppered Sans’ flushed face with kisses as the other’s entrance contracted around his shaft, squeezing it deliciously as his older brother got used to his size.

“paps, please!” Sans begged and he waited no longer before beginning a slow pace. The smaller monster was so tight and Papyrus feared he would not be able to last long. But that was alright. They had plenty of time to build up stamina and be together. Grasping the blue cock in his hand, he began pumping it as his hips sped up. His brother was perfect. He felt so divine. Their emotions sang through their bond as Papyrus panted, leaning down to claim Sans’ mouth in a deep kiss.

A particularly sharp cry was muffled by their mouths as Sans’ clamped tight around his rutting shaft, gripping him so tightly that he had to stop. Wet blue magic squirted over his pumping hand as his older brother came hard; his name along with curses lost in their kiss. Once the passage loosened enough for movement, Papyrus released his brother’s twitching shaft to angle Sans so that he wouldn’t harm his fragile hip.

Incoherent cries fell from between his sibling’s canines as he fucked the other monster’s oversensitive magic. Perhaps he did have a bit more stamina than Sans… But he was so close…!

“papyrus! please! come inside me, oh, please!”

His pace stuttered before he angled Sans up, ending a thrust to go as deeply as possible before he was moaning. Profanities he had never uttered in front of his brother bubbled out of his mouth as he released spurts of orange cum inside Sans. It filled the small channel up and spilled over, oozing down his sibling’s shaking femurs. Papyrus panted for air before opening his eyes and taking in just how beautiful Sans was in this moment. He didn’t bother to catch his breath or pull out of his brother before showering Sans with kisses.

“I love you so much, Sans. So much.” He murmured, “I have you. You will never be alone. I promise.”

And his brother, his overworked sibling who had suffered in silence for so very long smiled at him; happiness washing through their bond. \

 **Papyrus was happy and nothing else mattered** / _Sans was happy and nothing mattered._


	16. Chapter 16

**Summary for the Chapter:**

> I hope you enjoyed this origin story as much as I enjoyed writing it! <3 Thank you so much for your support, your comments and your kindness. This was my first fontcest fic that I took down for revision. And now it is finally done.
> 
> Thank you so much! ^_^
> 
> And if you want to interact with me, ask me questions or anything; please visit my Tumblr: mercy-run.tumblr.com

A week later, Sans finally checked his lab in their basement. He was still a little miffed that Alphys had his notes and that his research had been messed with. But there was still one place that had a small device he had crafted himself. A quick check in the second drawer confirmed that it hadn’t been removed. Pressing in a quick key-code, the small skeleton checked the graphs that had been running.

There were no fluctuations in the information here.

Flowey hadn’t been messing with time for a very long while. No loads or resets. Perhaps he had grown bored? The evil creature had seemed to be tiring of the same thing over and over whenever they had interacted.

Had he finally ran out of ‘games’ to play?

While Sans was certain his soul bond with Papyrus would enable his brother to remember through a reset, that didn’t mean he wanted one to happen. Putting the device away; the small skeleton smiled tentatively. If anything happened…he wasn’t alone anymore.

 

* * *

 

Sans had never expected a human to ever fall to the Underground. He walked up behind the child after the skeleton had instructed them to turn around and greet him properly. The whoopee cushion hidden in his palm was the only ‘ice-breaker’ the monster could think of that may ease the human’s worries. He had made a promise to the lady behind the door to protect this kid. The child turned, expression blank other than a barely perceptible tension to their mouth. They reached out and their hands met-

An obnoxious sound cut through the forest and Sans chuckled nervously, watching the kid closely. Their neutral expression dissolved into shock, mouth falling open before tinkling laughter shook the human’s shoulders, expression brightening as they brought their sleeves up to muffle their voice.

Maybe humans weren’t so bad after all... Anyone who could appreciate a bad joke was good in his book. Sans shoved his hands into his pockets.

“heh. the whoopee cushion in the hand trick. works every time.”

Perhaps… His eye-lights trailed up the path, over their shoulders to see Papyrus approaching them. Maybe after everything, they could finally have a happy ending and reach the surface. As the kid darted behind the conveniently shaped lamp; Sans felt a spark of hope ignite in his soul. That would be the best probability.

**-FIN**

 


End file.
